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Release notes listed here provide information about the current release of the OS MasterMap Topography Layer product and the previous nine releases.
This release note provides information about the November 2024 release of OS MasterMap (OSMM) Topography Layer.
This release note provides information about the September 2024 release of OS MasterMap (OSMM) Topography Layer.
This release note provides information about the August 2024 release of OS MasterMap (OSMM) Topography Layer.
This release note provides information about the June 2024 release of OS MasterMap (OSMM) Topography Layer.
This release note provides information about the May 2024 release of OS MasterMap (OSMM) Topography Layer.
This release note provides information about the April 2024 release of OS MasterMap (OSMM) Topography Layer.
This release note provides information about the February 2024 release of OS MasterMap (OSMM) Topography Layer.
This release note provides information about the January 2024 release of OS MasterMap (OSMM) Topography Layer.
This release note provides information about the November 2023 release of OS MasterMap (OSMM) Topography Layer.
This release note provides information about the October 2023 release of OS MasterMap (OSMM) Topography Layer.
OS MasterMap Topography Layer is the most detailed and accurate view of Great Britain's landscape. It includes features representing the manmade and natural environment, including: land cover, buildings, water, rail, height, heritage, structures, administrative boundaries, and roads, tracks and paths.
This product is updated every six weeks
The OS MasterMap Topography layer is presented seamlessly with more than 500 Million real world objects – all uniquely identified – including roads, buildings, parks and waterways. All data is managed and maintained by Ordnance Survey within one of the world’s largest spatial databases.
OS MasterMap Topography Layer gives you the confidence to make location-based decisions about assets, services, environmental risks, customers and operations.
All features are assigned a unique Topographic Identifier (TOID) to allow assets to be geo-tagged. This makes it ideal for monitoring assets such as pipelines, pylons, bridges and warehouses.
OS MasterMap Topography Layer includes enhanced features such as Building Height Attribute, enabling users to analyse the built environment, and Sites Layer showing the main points of access to key sites.
With OS MasterMap Topography Layer, each feature is a record in a database. Each of these records has information about the feature’s position and shape on Earth – its geometry – as well as details about it termed ‘attributes’. It provides an accurate visual context to help you interpret addresses, routes and imagery provided by the other layers.
The user may use the Topography Layer in a wide variety of ways, including:
Improving a user’s data capture processes and the accuracy of a user’s own derived data.
Aiding the visual clarity of data and the visual interpretation of data.
Achieving consistency and maintainable standards within geographic data holdings.
Enhancing the queries that can be run on their data and so providing better information for decision making.
Establishing a common reference between a user’s own datasets and data they may wish to share with other organisations.
Using the products in an integrated manner to derive additional information.
Identifying and managing change in their area of interest.
Creating historical views of their area of interest.
A common use for the product is by organisations who have their own GI and wish to examine it in relation to the real world around them. An example would be utility companies that have assets both at surface and below surface level. They frequently need to visit these assets, either for repair, maintenance or to add new assets. By viewing their infrastructure against the features in OS MasterMap Topography Layer, it will help their crews locate the assets, become familiar with the area before they leave their depot and allow them to provide a better user service by identifying those nearby premises that need to be notified about the works.
Access: Download
Data theme: Buildings, Land, Land Use, Structures, Transport, Water, Administrative and Statistical Units
Data structure: Vector – Identifiers
Coverage: Great Britain
Scale: 1:1 250 to 1:10 000
Format: GML 2.1.2, GeoPackage, Vector Tiles
Ordering area: All of Great Britain or customisable area (5 km² tiles or user-defined polygon)
OS Data Hub plan: Premium Plan, Public Sector Plan
OS MasterMap Topography Layer was developed in response to the need for a national topographic dataset that offers users a more sophisticated type of data that represented the world in a more realistic way and was more aligned to the increasing use and functionality of GIS and spatial technology with organisations.
Every feature within OS MasterMap has a TOID (TOpographic IDentifier) as the unique reference. This makes it possible to identify any single feature within the dataset with no ambiguity.
Alternative referencing systems can be subject to interpretation between organisations and users, leading to challenges in accurately matching data when exchanging information with others. TOIDs provide a persistent reference throughout a features lifecycle; even if a feature undergoes change the TOID remains the same. This allows customers to link their own data and track change over time.
Having unique references is essential to making the most out of storing data within a national data repository, as these rely on unique referencing to be able to store, sort, manage, query and retrieve data efficiently.
Please see our real-world object catalogue (PDF). It lists every type of real-world object in the OS MasterMap Topography Layer specification, and details how it is represented by Topography Layer features.
We define accuracy in three ways:
Absolute accuracy – how closely the coordinates of a point in the dataset agree with the coordinates of the same point on the ground (in the British National Grid reference system).
Relative accuracy – positional consistency of a data point or feature in relation to other local data points or features within the same or another reference dataset.
Geometric fidelity – the ‘trueness’ of features to the shapes and alignments of the objects they represent when testing the data according to the dataset specification against the ‘real world’ or reference dataset.
For cartographic representation, OS MasterMap Topography Layer is captured and designed for display at 1:1 250, 1:2 500 and 1:10 000 scales in urban, rural and mountain/moorland areas respectively.
In GIS OS MasterMap can be viewed over a considerable range of scales. The most scale-sensitive feature types, such as cartographic text and symbol features, are fixed in size and rapidly become less clear at smaller display scales (that is, when zoomed out).
OS MasterMap Topography Layer is also suitable for use in non–cartographic applications where the concept of scale is less applicable.
Read information about our policy for updating large-scale data, directly affecting OS MasterMap Topography Layer. Learn how we prioritise revision activity, and view the currency, definition, and criteria of categories of change.
You can find additional information and documentation about the OS MasterMap Topography Layer product on the 'OS MasterMap Topography Layer Product Support page' on the OS website.
We recommend you read the following guides:
Additional information and guidance about geographic information systems (GIS) is available on the 'Geographic Information Systems page' of the OS website.
Access to this product is free for PSGA members. Find out if you are a PSGA member or download a sample of OS MasterMap Topography Layer data by visiting the Topography layer product page here with links to all of the relevant resources. Alternatively, you can try out the full product by applying for a Data Exploration license here.
This release note provides information about the latest release of OS MasterMap (OSMM) Topography Layer, released to customers on 04 November 2024.
The following table contains product counts for this release of OSMM Topography Layer data. The dates shown are extraction dates, not release dates.
OSMM Topography Layer | Count on 05/09/2024 (Previous release) | Count on 17/10/2024 (Current release) |
---|---|---|
Numerous TOIDs (Topographic Identifiers) have changed since the last refresh, resulting in a visual difference in the data. The list below shows a sample of changed TOIDs and their locations that you can use as 'lookup samples' to validate that your latest supply has updated correctly:
In this release 7 errors were detected, of which, 2 have existed since the previous refresh. These are all considered to be minor errors and there are no major errors present.
We aim to have all errors resolved prior to the next release as part of ongoing quality improvements.
The next release of OS MasterMap Topography Layer is scheduled for 16 December 2024.
The land cover specification for rural geographies has been refined. The Mountain and Moorland refinement was completed in 2022.
The rural geography updates began capture in May 2022. The initial updates fed through to the July 2022 release of OSMM Topography Layer, with the multi class land cover polygons completed in December 2022. The single class land cover polygons will continue to feed through to product from April 2023.
The following two tables articulate this specification refinement:
The asterisk symbol (*) shows which criteria have been refined.
The land cover specification refinement means that the rural land cover data within OSMM Topography Layer will become more granular, producing a more detailed view made up of smaller more numerous polygons. This provides users with more accurate data that meets each individual’s specific requirements. These changes are purely refinements and do not change the data attribution.
Annex A shows three examples of how the rural land cover refinement is being translated into OSMM Topography Layer.
This release note provides information about the latest release of OS MasterMap (OSMM) Topography Layer, released to customers on 13 May 2024.
The following table contains product counts for this release of OSMM Topography Layer data. The dates shown are extraction dates, not release dates.
OSMM Topography Layer | Count on 14/03/2024 (Current release) | Count on 25/04/2024 (Current release) |
---|---|---|
In this release 10 minor errors were detected, of which 2 have existed since the previous refresh. All errors are considered to be minor errors. We aim to have all errors resolved prior to the next release as part of ongoing quality improvement.
The land cover specification for rural geographies has been refined. The Mountain and Moorland refinement was completed in 2022.
The rural geography updates began capture in May 2022. The initial updates fed through to the July 2022 release of OSMM Topography Layer, with the multi class land cover polygons completed in
December 2022. The single class land cover polygons will continue to feed through to product from April 2023.
The following two tables articulate this specification refinement:
The asterisk symbol (*) shows which criteria have been refined.
The land cover specification refinement means that the rural land cover data within OSMM Topography Layer will become more granular, producing a more detailed view made up of smaller, more numerous polygons. This provides users with more accurate data that meets each individual’s specific requirements. These changes are purely refinements and do not change the data attribution.
Annex A shows three examples of how the rural land cover refinement is being translated into OSMM Topography Layer.
Numerous TOIDs (Topographic Identifiers) have changed since the last refresh, resulting in a visual difference in the data. The list below shows a sample of changed TOIDs and their locations that you can use as 'lookup samples' to validate that your latest supply has updated correctly:
The next release of OS MasterMap Topography Layer is scheduled for 24 June 2024.
This release note provides information about the latest release of OS MasterMap (OSMM) Topography Layer, released to customers on 02 April 2024.
The following table contains product counts for this release of OSMM Topography Layer data. The dates shown are extraction dates, not release dates.
OSMM Topography Layer | Count on 01/02/2024 (Previous release) | Count on 14/03/2024 (Current release) |
---|
9 minor errors were detected, which is 2 more than were found in the last refresh. Of these 9 errors, 2 have existed since the previous refresh. All errors are considered to be minor errors. We aim to have all errors resolved prior to the next release as part of ongoing quality improvement.
The land cover specification for rural geographies has been refined. The Mountain and Moorland refinement was completed in 2022.
The rural geography updates began capture in May 2022. The initial updates fed through to the July 2022 release of OSMM Topography Layer, with the multi class land cover polygons completed in December 2022. The single class land cover polygons will continue to feed through to product from April 2023.
The following two tables articulate this specification refinement:
The asterisk symbol (*) shows which criteria have been refined.
The land cover specification refinement means that the rural land cover data within OSMM Topography Layer will become more granular, producing a more detailed view made up of smaller, more numerous polygons. This provides users with more accurate data that meets each individual’s specific requirements. These changes are purely refinements and do not change the data attribution.
Numerous TOIDs (Topographic Identifiers) have changed since the last refresh, resulting in a visual difference in the data. The list below shows a sample of changed TOIDs and their locations that you can use as 'lookup samples' to validate that your latest supply has updated correctly:
The next release of OS MasterMap Topography Layer is scheduled for 13 May 2024.
This release note provides information about the latest release of OS MasterMap (OSMM) Topography Layer, released to customers on 23 September 2024.
The following table contains product counts for this release of OSMM Topography Layer data. The dates shown are extraction dates, not release dates.
OSMM Topography Layer | Count on 25/07/2024 (Previous release) | Count on 05/09/2024 (Current release) |
---|
Numerous TOIDs (Topographic Identifiers) have changed since the last refresh resulting in a visual difference in the data. The list below shows a sample of changed TOIDs and their locations that you can use as 'lookup samples' to validate that your latest supply has updated correctly:
In this release 23 errors were detected, of which, 2 have existed since the previous refresh. These are all considered to be minor errors and there are no major errors present.
We aim to have all errors resolved prior to the next release as part of ongoing quality improvements.
The next release of OS MasterMap Topography Layer is scheduled for 04 November 2024.
The land cover specification for rural geographies has been refined. The Mountain and Moorland refinement was completed in 2022.
The rural geography updates began capture in May 2022. The initial updates fed through to the July 2022 release of OSMM Topography Layer, with the multi class land cover polygons completed in December 2022. The single class land cover polygons will continue to feed through to product from April 2023.
The following two tables articulate this specification refinement:
The asterisk symbol (*) shows which criteria have been refined.
The land cover specification refinement means that the rural land cover data within OSMM Topography Layer will become more granular, producing a more detailed view made up of smaller more numerous polygons. This provides users with more accurate data that meets each individual’s specific requirements. These changes are purely refinements and do not change the data attribution.
Annex A shows three examples of how the rural land cover refinement is being translated into OSMM Topography Layer.
This release note provides information about the latest release of OS MasterMap (OSMM) Topography Layer, released to customers on 19 February 2024.
The following table contains product counts for this release of OSMM Topography Layer data. The dates shown are extraction dates, not release dates.
OSMM Topography Layer | Count on 14/12/2023 (Previous Release) | Count on 01/02/2024 (Current Release) |
---|
In this release 7 minor errors were detected, which is 1 more than the 6 errors found in the last refresh. Of these errors, 1 has existed since the previous refresh. 6 of these are minor issues – these are minor issues with no visible issues, and there is 1 serious error of a double digitised line.
We aim to have all errors resolved prior to the next release as part of ongoing quality improvements.
The land cover specification for rural geographies has been refined. The Mountain and Moorland refinement was completed in 2022.
The rural geography updates began capture in May 2022. The initial updates fed through to the July 2022 release of OSMM Topography Layer, with the multi class land cover polygons completed in December 2022. The single class land cover polygons will continue to feed through to product from April 2023.
The following two tables articulate this specification refinement:
The asterisk symbol (*) shows which criteria have been refined.
The land cover specification refinement means that the rural land cover data within OSMM Topography Layer will become more granular, producing a more detailed view made up of smaller more numerous polygons. This provides users with more accurate data that meets each individual’s specific requirements. These changes are purely refinements and do not change the data attribution.
Numerous TOIDs (Topographic Identifiers) have changed since the last refresh, resulting in a visual difference in the data. The list below shows a sample of changed TOIDs and their locations that you can use as 'lookup samples' to validate that your latest supply has updated correctly:
The next release of OS MasterMap Topography Layer is scheduled for 02 April 2024.
This release note provides information about the latest release of OS MasterMap (OSMM) Topography Layer, released to customers on 04 January 2024
The following table contains product counts for this release of OSMM Topography Layer data. The dates shown are extraction dates, not release dates.
OSMM Topography Layer | Count on 02/11/2023 (Previous Release) | Count on 14/12/2023 (Current Release) |
---|
In this release 6 minor errors were detected, which is 20 less than the 26 errors found in the last refresh. Of these errors, 2 have existed since the previous refresh – these are minor issues caused by conflict (where the geometry of adjacent feature has not been updated to match), but there are no visible issues.
The land cover specification for rural geographies has been refined. The Mountain and Moorland refinement was completed in 2022.
The rural geography updates began capture in May 2022. The initial updates fed through to the July 2022 release of OSMM Topography Layer, with the multi class land cover polygons completed in December 2022. The single class land cover polygons will continue to feed through to product from April 2023.
The following two tables articulate this specification refinement:
The asterisk symbol (*) shows which criteria have been refined.
The land cover specification refinement means that the rural land cover data within OSMM Topography Layer will become more granular, producing a more detailed view made up of smaller more numerous polygons. This provides users with more accurate data that meets each individual’s specific requirements. These changes are purely refinements and do not change the data attribution.
Numerous TOIDs (Topographic Identifiers) have changed since the last refresh, resulting in a visual difference in the data. The list below shows a sample of changed TOIDs and their locations that you can use as 'lookup samples' to validate that your latest supply has updated correctly:
The next release of OS MasterMap Topography Layer is scheduled for 19 February 2024.
The latest refresh dates for OS MasterMap Topography Layer data
This release note provides information about the latest release of OS MasterMap (OSMM) Topography Layer, released to customers on 20 November 2023.
The following table contains product counts for this release of OSMM Topography Layer data. The dates shown are extraction dates, not release dates.
OSMM Topography Layer | Count on 21/09/2023 (Previous Release) | Count on 02/11/2023 (Current Release) |
---|
26 minor errors were detected, which is 22 more than the 48 errors found in the last refresh. Of these errors, 3 have existed since the previous refresh – these are minor issues caused by conflict (where the geometry of adjacent feature has not been updated to match), but there are no visible issues.
An issue has been identified whereby Post Offices are being incorrectly attributed or deleted due to data misinterpretation. In the previous release over 1 100 affected Post Offices were noted. As a result, there are 966 remaining without cartographic text of ‘Post Office’ or ‘PO’ in the November 2023 release of OSMM Topography Layer. A solution is currently being implemented for this issue and we aim to rectify it as soon as possible.
The land cover specification for rural geographies has been refined. The Mountain and Moorland refinement was completed in 2022.
The rural geography updates began capture in May 2022. The initial updates fed through to the July 2022 release of OSMM Topography Layer, with the multi class land cover polygons completed in December 2022. The single class land cover polygons will continue to feed through to product from April 2023.
The following two tables articulate this specification refinement:
The asterisk symbol (*) shows which criteria have been refined.
The land cover specification refinement means that the rural land cover data within OSMM Topography Layer will become more granular, producing a more detailed view made up of smaller more numerous polygons. This provides users with more accurate data that meets each individual’s specific requirements. These changes are purely refinements and do not change the data attribution.
Annex A shows three examples of how the rural land cover refinement is being translated into OSMM Topography Layer.
Numerous TOIDs (Topographic Identifiers) have changed since the last refresh, resulting in a visual difference in the data. The list below shows a sample of changed TOIDs and their locations that you can use as 'lookup samples' to validate that your latest supply has updated correctly:
The next release of OS MasterMap Topography Layer is scheduled for 04 January 2024.
This release note provides information about the latest release of OS MasterMap (OSMM) Topography Layer, released to customers on 09 October 2023.
The following table contains product counts for this release of OSMM Topography Layer data. The dates shown are extraction dates, not release dates.
OSMM Topography Layer | Count on 10/08/2023 (Previous Release) | Count on 21/09/2023 (Current Release) |
---|
48 minor errors were detected, which is 12 more than the 36 errors found in the last refresh. Of these errors, 4 have existed since the previous refresh – these are minor issues caused by conflict (where the geometry of adjacent feature has not been updated to match), but there are no visible issues.
An issue has been identified whereby post offices are being incorrectly attributed or deleted due to data misinterpretation. In the previous release over 1 100 reclassified / deleted post offices were noted. There are 966 of these errors remaining in the October 2023 release. This may result in the carto text ‘Post Office’ or ‘PO’ missing from OSMM Topography Layer. A solution is currently being investigated for this issue and we aim to rectify it as soon as possible.
The land cover specification for rural geographies has been refined. The Mountain and Moorland refinement was completed in 2022.
The rural geography updates began capture in May 2022. The initial updates fed through to the July 2022 release of OSMM Topography Layer, with the multi class land cover polygons completed in December 2022. The single class land cover polygons will continue to feed through to product from April 2023.
The following two tables articulate this specification refinement:
The asterisk symbol (*) shows which criteria have been refined.
The land cover specification refinement means that the rural land cover data within OSMM Topography Layer will become more granular, producing a more detailed view made up of smaller more numerous polygons. This provides users with more accurate data that meets each individual’s specific requirements. These changes are purely refinements and do not change the data attribution.
Numerous TOIDs (Topographic Identifiers) have changed since the last refresh, resulting in a visual difference in the data. The list below shows a sample of changed TOIDs and their locations that you can use as 'lookup samples' to validate that your latest supply has updated correctly:
The next release of OS MasterMap Topography Layer is scheduled for 20 November 2023.
This overview introduces OS MasterMap Topography Layer and gives context for all users – highlighting key features, providing examples of uses, and listing details such as file sizes, formats, etc.
OS MasterMap Topography Layer contains features that represent objects in the physical environment, such as buildings, fields, fences, and letter boxes. It also includes intangible objects, such as county boundaries and the lines of mean high or low waters. There are over 500 million features in the product. Coverage includes the whole of Great Britain (i.e. England, Scotland, and Wales).
The key characteristics and benefits of OS MasterMap Topography Layer are:
Individual real-world topographic features are represented by points, lines, and polygons, each with their own unique reference, called a topographic identifier (TOID).
Each uniquely referenced feature has attribution that provides information about the real-world object it represents and metadata that tracks changes to the feature’s lifecycle.
It employs a scale of data capture appropriate to the density of features – the higher the number of features within an area, the larger the scale used to survey them – ensuring the detail of individual features can be shown and with coordinates delivered in British National Grid (with the exception of vector tiles format, which is supplied in Web Mercator projection – EPSG:3857).
The data is developed, managed and maintained by Ordnance Survey within one of the world’s largest spatial databases.
The data is delivered as a seamless, geographically contiguous area for the whole of Great Britain.
These characteristics mean that a user may use the product in a wide variety of ways, including:
Improving the accuracy of their own derived data.
Improving their data capture processes.
Creating consistency and achieving maintainable standards within geographic data holdings.
Establishing a common reference between their own datasets and data they may wish to share with other organisations.
Improving the visual clarity of data and aiding the visual interpretation of data.
Using OS products in an integrated manner to derive additional information. For example, appending OS AddressBase data to OS MasterMap Topography Layer buildings data to derive building names and addresses.
Identifying and managing change in their area of interest (AOI).
Creating historical views of their AOI.
Enhancing the queries that can be run on their data, thereby providing better information for decision making.
This overview document provides a high-level introduction to OS MasterMap Topography layer and covers the following topics:
TOID | Location (i.e. XY coordinates) |
---|---|
Geographic area | Minimum area size for land cover | Minimum width |
---|---|---|
Geographic area | Minimum area size for land cover | Minimum width |
---|---|---|
Geographic area | Minimum area size for land cover | Minimum width |
---|---|---|
Geographic area | Minimum area size for land cover | Minimum width |
---|---|---|
TOID | Location (i.e. XY coordinates) |
---|---|
Geographic area | Minimum area size for land cover | Minimum width |
---|
Geographic area | Minimum area size for land cover | Minimum width |
---|
shows three examples of how the rural land cover refinement is being translated into OSMM Topography Layer.
TOID | Location (i.e. XY coordinates) |
---|
Alongside GML format, OSMM Topography Layer is also available in GeoPackage and vector tiles formats (from March 2023). Please see the and guides for more information on using these new formats. The product is supplied as an online download. You can download data in its various formats from the .
Geographic Area | Minimum Area Size for Land Cover | Minimum width |
---|
Geographic area | Minimum Area Size for Land Cover | Minimum Width |
---|
shows three examples of how the rural land cover refinement is being translated into OSMM Topography Layer.
TOID | Location (i.e. XY coordinates) |
---|
Alongside GML format, OSMM Topography Layer is also available in GeoPackage and vector tiles formats (from March 2023). Please see the and guides for more information on using these new formats. The product is supplied as an online download. You can download data in its various formats from the .
Geographic Area | Minimum Area Size for Land Cover | Minimum Width |
---|
Geographic Area | Minimum Area Size for Land Cover | Minimum Width |
---|
shows three examples of how the rural land cover refinement is being translated into OSMM Topography Layer.
TOID | Location (i.e. XY coordinates) |
---|
Alongside GML format, OSMM Topography Layer is also available in GeoPackage and vector tiles formats (from March 2023). Please see the and guides for more information on using these new formats. The product is supplied as an online download. You can download data in its various formats from the .
Geographic Area | Minimum Area Size for Land Cover | Minimum Width |
---|
Geographic Area | Minimum Area Size for Land Cover | Minimum Width |
---|
TOID | Location (i.e. XY coordinates) |
---|
Alongside GML format, OSMM Topography Layer is also available in GeoPackage and vector tiles formats (from March 2023). Please see the and guides for more information on using these new formats. The product is supplied as an online download. You can download data in its various formats from the .
Geographic Area | Minimum Area Size for Land Cover | Minimum Width |
---|
Geographic Area | Minimum Area Size for Land Cover | Minimum Width |
---|
shows three examples of how the rural land cover refinement is being translated into OSMM Topography Layer.
TOID | Location (i.e. XY coordinates) |
---|
Total Feature Count
510 067 246
510 670 422
Count of Topo Area
127 597 512
127 758 433
Count of Topo Line
351 522 233
351 963 619
Count of Topo Point
4 390 130
4 391 190
Count of Topo Bline
527 717
524 557
Count of Topo CartoSym
3 785 178
3 780 899
Count of Topo CartoTxt
22 244 476
22 251 724
Total Count of Deletes
562 062
666 186
Count of Topo Area deletions
112 920
138 007
Count of Topo Line deletions
420 657
496 634
Count of Topo Point deletions
2 285
1 941
Count of Topo Bline deletions
3 344
3 858
Count of Topo CartoSym deletions
7 463
7 484
Count of Topo CartoTxt deletions
15 393
18 262
Total Count of Inserts
1 099 911
1 269 362
Count of Topo Area inserts
255 035
298 928
Count of Topo Line inserts
816 716
938 020
Count of Topo Point inserts
3 588
3 001
Count of Topo Bline inserts
444
698
Count of Topo CartoSym inserts
3 699
3 205
Count of Topo CartoTxt inserts
20 429
25 510
Total Count of Modifications
1 095 471
1 257 214
Count of Topo Area Modifications
550 327
643 905
Count of Topo Line Modifications
524 077
597 362
Count of Topo Point Modifications
262
275
Count of Topo Bline Modifications
7 426
2 456
Count of Topo CartoSym Modifications
18
53
Count of Topo CartoTxt Modifications
13 361
13 163
COU Size (bytes)
479 107 436
543 866 589
osgb5000005336454207
236466.509, 628118.225
osgb5000005196539006
329800.731, 477434.786
osgb5000005283135322
507039.113, 375158.152
osgb1000000381134706
128427.853, 919654.391
osgb1000000223021238
333046.984, 476824.072
osgb1000002503313612
518198.08, 452626.12
Urban
0.1hectares (ha) (1 000m²)
5m
Rural
0.1hectares (ha) (1 000m²)
10m
Mountain and moorland
1.0hectares (ha) (10 000m²)
10m
Urban
0.1hectares (ha) (1 000m²)
5m
Rural
0.1hectares (ha) (1 000m²)
5m*
Mountain and moorland
0.1hectares (ha) (1 000m²)*
5m*
Total Feature Count
507 879 548
508 329 170
Count of Topo Area
127 035 158
127 146 339
Count of Topo Line
349 942 731
350 253 247
Count of Topo Point
4 375 415
4 385 721
Count of Topo Bline
532 572
532 257
Count of Topo CartoSym
3 778 000
3 788 842
Count of Topo CartoTxt
22 215 672
22 222 764
Total Count of Deletes
363 259
387 625
Count of Topo Area deletions
75 296
78 038
Count of Topo Line deletions
253 444
277 326
Count of Topo Point deletions
4 059
3 039
Count of Topo Bline deletions
561
533
Count of Topo CartoSymcc deletions
8 953
6 393
Count of Topo CartoTxtcc deletions
20 946
22 296
Total Count of Inserts
866 957
837 247
Count of Topo Area inserts
198 781
189 219
Count of Topo Line inserts
595 718
587 842
Count of Topo Point inserts
17 417
13 345
Count of Topo Bline inserts
222
218
Count of Topo CartoSym inserts
23 256
17 235
Count of Topo CartoTxt inserts
31 563
29 388
Total Count of Modifications
634 202
736 646
Count of Topo Area Modifications
309 690
369 267
Count of Topo Line Modifications
308 659
353 690
Count of Topo Point Modifications
311
231
Count of Topo Bline Modifications
1 403
2 681
Count of Topo CartoSym Modifications
40
44
Count of Topo CartoTxt Modifications
14 099
10 733
COU Size (bytes)
336 114 289
333 062 363
Urban
0.1hectares (ha) (1 000m²)
5m
Rural
0.1hectares (ha) (1 000m²)
10m
Mountain and moorland
1.0hectares (ha) (10 000m²)
10m
Urban
0.1hectares (ha) (1 000m²)
5m
Rural
0.1hectares (ha) (1 000m²)
5m*
Mountain and moorland
0.1hectares (ha) (1 000m²)*
5m*
osgb1000000182286603
339097.4, 551740.35
osgb5000005285000934
459029.88, 402617.33
osgb1000002318155560
533464.054, 122925.909
osgb1000000302327200
207276.41, 691450.97
osgb5000005297224912
430701.235, 346985.231
osgb1000002081333910
596419.64, 208356.555
Total Feature Count | 507 375 850 | 507 879 548 |
Count of Topo Area | 126 911 673 | 127 035 158 |
Count of Topo Line | 349 600 457 | 349 942 731 |
Count of Topo Point | 4 362 057 | 4 375 415 |
Count of Topo Bline | 532 911 | 532 572 |
Count of Topo CartoSym | 3 763 697 | 3 778 000 |
Count of Topo CartoTxt | 22 205 055 | 22 215 672 |
Total Count of Deletes | 352 971 | 363 259 |
Count of Topo Area deletions | 72 340 | 75 296 |
Count of Topo Line deletions | 246 393 | 253 444 |
Count of Topo Point deletions | 4 698 | 4 059 |
Count of Topo Bline deletions | 433 | 561 |
Count of Topo CartoSymcc deletions | 11 208 | 8 953 |
Count of Topo CartoTxtcc deletions | 17 899 | 20 946 |
Total Count of Inserts | 811 142 | 866 957 |
Count of Topo Area inserts | 180 007 | 198 781 |
Count of Topo Line inserts | 551 663 | 595 718 |
Count of Topo Point inserts | 21 692 | 17 417 |
Count of Topo Bline inserts | 353 | 222 |
Count of Topo CartoSym inserts | 29 505 | 23 256 |
Count of Topo CartoTxt inserts | 27 922 | 31 563 |
Total Count of Modifications | 600 677 | 634 202 |
Count of Topo Area Modifications | 294 892 | 309 690 |
Count of Topo Line Modifications | 291 597 | 308 659 |
Count of Topo Point Modifications | 326 | 311 |
Count of Topo Bline Modifications | 628 | 1 403 |
Count of Topo CartoSym Modifications | 132 | 40 |
Count of Topo CartoTxt Modifications | 13 102 | 14 099 |
COU Size (bytes) | 386 470 897 | 336 114 289 |
Urban | 0.1hectares (ha) (1 000m²) | 5m |
Rural | 0.1hectares (ha) (1 000m²) | 10m |
Mountain and moorland | 1.0hectares (ha) (10 000m²) | 10m |
Urban | 0.1hectares (ha) (1 000m²) | 5m |
Rural | 0.1hectares (ha) (1 000m²) | 5m* |
Mountain and moorland | 0.1hectares (ha) (1 000m²)* | 5m* |
TOID | Location (i.e. XY coordinates) |
osgb5000005109728428 | 322926.508, 704955.071 |
oosgb5000005252408974 | 396225, 4754643 |
osgb1000000030598131 | 504443.618, 242017.376 |
osgb1000000293839535 | 203531.7, 862031.28 |
osgb5000005299999425 | 406660.07, 436264.33 |
osgb5000005243520249 | 505688.732, 484331.45 |
Total Feature Count | 509 529 397 | 510 067 246 |
Count of Topo Area | 127 455 397 | 127 597 512 |
Count of Topo Line | 351 126 174 | 351 522 233 |
Count of Topo Point | 4 388 827 | 4 390 130 |
Count of Topo Bline | 530 617 | 527 717 |
Count of Topo CartoSym | 3 788 942 | 3 785 178 |
Count of Topo CartoTxt | 22 239 440 | 22 244 476 |
Total Count of Deletes | 636 733 | 562 062 |
Count of Topo Area deletions | 129 723 | 112 920 |
Count of Topo Line deletions | 478 982 | 420 657 |
Count of Topo Point deletions | 2 227 | 2 285 |
Count of Topo Bline deletions | 1 374 | 3 344 |
Count of Topo CartoSym deletions | 4 265 | 7 463 |
Count of Topo CartoTxt deletions | 20 162 | 15 393 |
Total Count of Inserts | 1 283 294 | 1 099 911 |
Count of Topo Area inserts | 295 954 | 255 035 |
Count of Topo Line inserts | 949 436 | 816 716 |
Count of Topo Point inserts | 3 017 | 3 588 |
Count of Topo Bline inserts | 664 | 444 |
Count of Topo CartoSym inserts | 3 336 | 3 699 |
Count of Topo CartoTxt inserts | 30 887 | 20 429 |
Total Count of Modifications | 1 213 405 | 1 095 471 |
Count of Topo Area Modifications | 611 739 | 550 327 |
Count of Topo Line Modifications | 585 817 | 524 077 |
Count of Topo Point Modifications | 256 | 262 |
Count of Topo Bline Modifications | 1 485 | 7 426 |
Count of Topo CartoSym Modifications | 51 | 18 |
Count of Topo CartoTxt Modifications | 14 057 | 13 361 |
COU Size (bytes) | 539 082 200 | 479 107 436 |
osgb1000000293853171 | 276700.84, 892218.39 |
osgb5000005126441008 | 399800.555, 403814.06 |
osgb5000005194435102 | 570821, 186280 |
osgb1000002574125339 | 311521.93, 529487.37 |
osgb5000005216534775 | 345159.916, 464018.662 |
osgb5000005307345670 | 520838.36, 249433.06 |
Geographic area | Minimum area size for land cover | Minimum width |
Urban | 0.1hectares (ha) (1 000m²) | 5m |
Rural | 0.1hectares (ha) (1 000m²) | 10m |
Mountain and moorland | 1.0hectares (ha) (10 000m²) | 10m |
Geographic area | Minimum area size for land cover | Minimum width |
Urban | 0.1hectares (ha) (1 000m²) | 5m |
Rural | 0.1hectares (ha) (1 000m²) | 5m* |
Mountain and moorland | 0.1hectares (ha) (1 000m²)* | 5m* |
Total Feature Count | 506 917 679 | 507 375 850 |
Count of Topo Area | 126 804 006 | 126 911 673 |
Count of Topo Line | 349 295 187 | 349 600 457 |
Count of Topo Point | 4 345 063 | 4 362 057 |
Count of Topo Bline | 532 991 | 532 911 |
Count of Topo CartoSym | 3 745 400 | 3 763 697 |
Count of Topo CartoTxt | 22 195 032 | 22 205 055 |
Total Count of Deletes | 333 884 | 352 971 |
Count of Topo Area deletions | 70 410 | 72 340 |
Count of Topo Line deletions | 231 489 | 246 393 |
Count of Topo Point deletions | 3 420 | 4 698 |
Count of Topo Bline deletions | 828 | 433 |
Count of Topo CartoSymcc deletions | 7 670 | 11 208 |
Count of Topo CartoTxtcc deletions | 20 067 | 17 899 |
Total Count of Inserts | 767 416 | 811 142 |
Count of Topo Area inserts | 176 713 | 180 007 |
Count of Topo Line inserts | 526 812 | 551 663 |
Count of Topo Point inserts | 15 012 | 21 692 |
Count of Topo Bline inserts | 391 | 353 |
Count of Topo CartoSym inserts | 18 520 | 29 505 |
Count of Topo CartoTxt inserts | 29 968 | 27 922 |
Total Count of Modifications | 515 536 | 600 677 |
Count of Topo Area Modifications | 246 717 | 294 892 |
Count of Topo Line Modifications | 254 055 | 291 597 |
Count of Topo Point Modifications | 254 | 326 |
Count of Topo Bline Modifications | 955 | 628 |
Count of Topo CartoSym Modifications | 45 | 132 |
Count of Topo CartoTxt Modifications | 13 510 | 13 102 |
COU Size (bytes) | 347 863 984 | 386 470 897 |
Urban | 0.1hectares (ha) (1 000m²) | 5m |
Rural | 0.1hectares (ha) (1 000m²) | 10m |
Mountain and moorland | 1.0hectares (ha) (10 000m²) | 10m |
Urban | 0.1hectares (ha) (1 000m²) | 5m |
Rural | 0.1hectares (ha) (1 000m²) | 5m* |
Mountain and moorland | 0.1hectares (ha) (1 000m²)* | 5m* |
osgb1000000175416836 | 332000, 721912.22 |
osgb1000000230216079 | 335945.87, 440115.421 |
osgb5000005128685631 | 578813.895, 172187.251 |
osgb5000005327816366 | 265014.445, 842929.902 |
osgb5000005328747598 | 400486.093, 278819.54 |
osgb5000005154766496 | 617199.12, 165232.91 |
Total Feature Count | 506 484 147 | 506 917 679 |
Count of Topo Area | 126 697 703 | 126 804 006 |
Count of Topo Line | 348 999 864 | 349 295 187 |
Count of Topo Point | 4 333 471 | 4 345 063 |
Count of Topo Bline | 533 428 | 532 991 |
Count of Topo CartoSym | 3 734 550 | 3 745 400 |
Count of Topo CartoTxt | 22 185 131 | 22 195 032 |
Total Count of Deletes | 482 784 | 333 884 |
Count of Topo Area deletions | 78 620 | 70 410 |
Count of Topo Line deletions | 360 998 | 231 489 |
Count of Topo Point deletions | 3 993 | 3 420 |
Count of Topo Bline deletions | 591 | 828 |
Count of Topo CartoSymcc deletions | 9 635 | 7 670 |
Count of Topo CartoTxtcc deletions | 28 947 | 20 067 |
Total Count of Inserts | 915 049 | 767 416 |
Count of Topo Area inserts | 214 888 | 176 713 |
Count of Topo Line inserts | 624 246 | 526 812 |
Count of Topo Point inserts | 16 055 | 15 012 |
Count of Topo Bline inserts | 398 | 391 |
Count of Topo CartoSym inserts | 21 829 | 18 520 |
Count of Topo CartoTxt inserts | 37 633 | 29 968 |
Total Count of Modifications | 681 711 | 515 536 |
Count of Topo Area Modifications | 289 725 | 246 717 |
Count of Topo Line Modifications | 369 012 | 254 055 |
Count of Topo Point Modifications | 374 | 254 |
Count of Topo Bline Modifications | 674 | 955 |
Count of Topo CartoSym Modifications | 57 | 45 |
Count of Topo CartoTxt Modifications | 21 869 | 13 510 |
COU Size (bytes) | 402 922 509 | 347 863 984 |
Urban | 0.1hectares (ha) (1 000m²) | 5m |
Rural | 0.1hectares (ha) (1 000m²) | 10m |
Mountain and moorland | 1.0hectares (ha) (10 000m²) | 10m |
Urban | 0.1hectares (ha) (1 000m²) | 5m |
Rural | 0.1hectares (ha) (1 000m²) | 5m* |
Mountain and moorland | 0.1hectares (ha) (1 000m²)* | 5m* |
osgb1000000168404255 | 328579.99, 958515.98 |
osgb5000005152517605 | 348374.945, 431019.423 |
osgb1000001824692637 | 541419.437, 101834.574 |
osgb1000000385134315 | 188967, 835637.5 |
osgb5000005299962750 | 416833.55, 444757.47 |
osgb1000000013827617 | 508743.536, 482017.503 |
Total Feature Count | 506 051 882 | 506 484 147 |
Count of Topo Area | 126 561 435 | 126 697 703 |
Count of Topo Line | 348 736 616 | 348 999 864 |
Count of Topo Point | 4 321 409 | 4 333 471 |
Count of Topo Bline | 533 621 | 533 428 |
Count of Topo CartoSym | 3 722 356 | 3 734 550 |
Count of Topo CartoTxt | 22 176 445 | 22 185 131 |
Total Count of Deletes | 552 193 | 482 784 |
Count of Topo Area deletions | 90 968 | 78 620 |
Count of Topo Line deletions | 413 319 | 360 998 |
Count of Topo Point deletions | 4 058 | 3 993 |
Count of Topo Bline deletions | 1 023 | 591 |
Count of Topo CartoSymcc deletions | 9 835 | 9 635 |
Count of Topo CartoTxtcc deletions | 32 990 | 28 947 |
Total Count of Inserts | 972 994 | 915 049 |
Count of Topo Area inserts | 225 863 | 214 888 |
Count of Topo Line inserts | 672 929 | 624 246 |
Count of Topo Point inserts | 14 334 | 16 055 |
Count of Topo Bline inserts | 530 | 398 |
Count of Topo CartoSym inserts | 20 171 | 21 829 |
Count of Topo CartoTxt inserts | 39 167 | 37 633 |
Total Count of Modifications | 833 584 | 681 711 |
Count of Topo Area Modifications | 378 432 | 289 725 |
Count of Topo Line Modifications | 430 672 | 369 012 |
Count of Topo Point Modifications | 319 | 374 |
Count of Topo Bline Modifications | 1 190 | 674 |
Count of Topo CartoSym Modifications | 103 | 57 |
Count of Topo CartoTxt Modifications | 22 868 | 21 869 |
COU Size (bytes) | 413 944 082 | 402 922 509 |
Urban | 0.1hectares (ha) (1 000m²) | 5m |
Rural | 0.1hectares (ha) (1 000m²) | 10m |
Mountain and moorland | 1.0hectares (ha) (10 000m²) | 10m |
Urban | 0.1hectares (ha) (1 000m²) | 5m |
Rural | 0.1hectares (ha) (1 000m²) | 5m* |
Mountain and moorland | 0.1hectares (ha) (1 000m²)* | 5m* |
osgb1000000288205307 | 259068.6, 910831.5 |
osgb5000005183695974 | 410989.2, 439867.5 |
osgb1000002057136077 | 548427.559, 256068.45 |
osgb1000000168084341 | 310922.73, 967740.4 |
osgb1000000321127198 | 231400.028, 393013.406 |
osgb5000005103319502 | 549683.928, 349919.463 |
Total Feature Count | 505 631 081 | 506 051 882 |
Count of Topo Area | 126 426 540 | 126 561 435 |
Count of Topo Line | 348 477 006 | 348 736 616 |
Count of Topo Point | 4 311 133 | 4 321 409 |
Count of Topo Bline | 534 114 | 533 621 |
Count of Topo CartoSym | 3 712 020 | 3 722 356 |
Count of Topo CartoTxt | 22 170 268 | 22 176 445 |
Total Count of Deletes | 580 807 | 552 193 |
Count of Topo Area deletions | 93 938 | 90 968 |
Count of Topo Line deletions | 440 874 | 413 319 |
Count of Topo Point deletions | 4 722 | 4 058 |
Count of Topo Bline deletions | 689 | 1 023 |
Count of Topo CartoSymcc deletions | 10 421 | 9 835 |
Count of Topo CartoTxtcc deletions | 30 163 | 32 990 |
Total Count of Inserts | 963 518 | 972 994 |
Count of Topo Area inserts | 218 909 | 225 863 |
Count of Topo Line inserts | 672 774 | 672 929 |
Count of Topo Point inserts | 14 794 | 14 334 |
Count of Topo Bline inserts | 296 | 530 |
Count of Topo CartoSym inserts | 21 966 | 20 171 |
Count of Topo CartoTxt inserts | 34 779 | 39 167 |
Total Count of Modifications | 941 944 | 833 584 |
Count of Topo Area Modifications | 442 081 | 378 432 |
Count of Topo Line Modifications | 479 273 | 430 672 |
Count of Topo Point Modifications | 339 | 319 |
Count of Topo Bline Modifications | 665 | 1 190 |
Count of Topo CartoSym Modifications | 173 | 103 |
Count of Topo CartoTxt Modifications | 19 413 | 22 868 |
COU Size (bytes) | 418 831 687 | 413 944 082 |
Urban | 0.1hectares (ha) (1 000m²) | 5m |
Rural | 0.1hectares (ha) (1 000m²) | 10m |
Mountain and moorland | 1.0hectares (ha) (10 000m²) | 10m |
Urban | 0.1hectares (ha) (1 000m²) | 5m |
Rural | 0.1hectares (ha) (1 000m²) | 5m* |
Mountain and moorland | 0.1hectares (ha) (1 000m²)* | 5m* |
osgb5000005305675906 | 266453.432, 660668.531 |
osgb5000005121024361 | 297913.54, 337342.3 |
osgb5000005141832094 | 530516.838, 268540.61 |
osgb1000000390737946 | 140986.634, 699762.657 |
osgb1000002312456023 | 271311.2, 318049.66 |
osgb5000005282543279 | 614730.487, 257892.756 |
The Geography Markup Language (GML) and GeoPackage formats use the British National Grid (BNG) spatial reference system. BNG uses the OSGB36 (EPSG 27700) geodetic datum and a single Transverse Mercator projection for the whole of Great Britain. Positions on this projection are described using easting and northing coordinates in units of metres.
Vector tiles format is supplied in Web Mercator projection (EPSG:3857). Web Mercator projection uses WGS84 geodetic datum to render the vector tiles.
The More than Maps platform has an in-depth guide to coordinate reference systems and mapping using the British National Grid here.
OS MasterMap Topography Layer is used extensively by businesses and organisations that need to relate their activities and / or their assets to the physical environment.
One of the most common uses for the product is by organisations who have their own GI and wish to examine it in relation to the real world around them. An example would be utility companies that have assets both at surface level and below surface level. They frequently need to visit these assets, either for repair, maintenance, or to add new assets. By viewing their infrastructure against the features in
OS MasterMap Topography Layer, it will help their crews locate the assets and become familiar with the area before they leave their depot, and it will allow them to provide a better user service by identifying those nearby premises that need to be notified about the works.
Taking this a stage further, many organisations need to derive their own GI from OS MasterMap Topography Layer. They use the individual features that Ordnance Survey provide to form the building blocks for their own sets of GI. Many local- and central-government organisations use the data in this way. A local authority, for example, may use it to maintain a register of land and buildings in their ownership.
Once they have the physical feature or group of features they are interested in, they can attach their own attribution to that already provided with the product. When this kind of data association takes place, it can lead to efficiencies in storing and using data. It can also enable data to be shared more easily both between and within organisations.
As more GI is created, it is possible to analyse the spread and distribution of features or activities and learn from their relationship to other physical features. For example, a police force might plot the locations of certain types of street crimes, and by analysing the pattern and the timing of the incidents against the local topography, they may be able to target their resources more efficiently.
OS MasterMap Topography Layer can also be used as part of a data modelling or a predictive modelling tool. In addition, OS MasterMap Topography Layer is also used by organisations looking for areas where specific physical conditions exist. A retailer, for example, may use OS MasterMap Topography Layer to help them find a site for a new store by using the attribution to find land parcels of a certain size and distance from a settlement or main road and cross referencing the information contained within OS AddressBase to identify an ideal catchment area. Emergency planners may use OS MasterMap Topography Layer to assist in planning and preparing for emergencies by identifying the areas most likely to be affected. The product can also be used to model the sequence of events in any given type of emergency, so that their own resources and command centres are unlikely to be cut off or taken out of action by the emergency itself.
It is possible to customise OS MasterMap Topography Layer styling as a way of clearly communicating GI in reports and presentations. GI can be conveyed more meaningfully in a map than by text or tables, making it easier to get points across to many different types of audience, whether they are key decision-makers, people inside the organisation, or members of the public. OS maintains an OS MasterMap Topography Layer Stylesheets page on GitHub with predesigned, schema-specific styling guides for the product.
It should be noted that the ability of an organisation to develop any or all the applications mentioned above will depend, in part, on the systems they use. Most GIS are capable of performing, to a greater or lesser degree, the applications already mentioned. Examples of other product applications for OS MasterMap Topography Layer include the following:
Land management and property development
Site planning
Citizen services
Location-based services on mobile devices
Environmental monitoring
Tourism and promotional material
Risk assessment
User service centres
This section gives an overview of the nine themes of OS MasterMap Topography Layer:
Administrative Boundaries
Buildings
Heritage and Antiquities
Land
Rail
Roads, Tracks, and Paths
Structures
Terrain and Height
Water
The main features of each theme are described in the following sub-sections. More detailed information about the nine themes, including the rules that govern which theme or themes are assigned to a feature, can be found in the product's Technical Specification.
Wherever possible, real-world objects are represented in their true surveyed position. However, for the sake of clarity of display or plotting, real-world objects may be generalised (for example, small juts in house fronts may not be shown). The normal methods of generalisation that can be applied to features are:
Emphasis
Selection for inclusion
Simplification
Omission
Real-world objects may also be simplified in the OS MasterMap Topography Layer, for example, a small group of trees may be recorded as a single point or polygon feature. The following sub-sections give a breakdown, by feature type, of the nine themes in greater detail, including regional and cultural special designations.
Administrative boundaries are defined as showing the limits of responsibility and representation for electoral and administrative purposes. Boundary alignments are shown within the Administrative Boundaries theme. As well as the boundary’s relationship to real-world objects, its mereing and boundary descriptions, where needed for clarification, are also supplied.
Buildings are defined as permanent roofed constructions, usually with walls. This includes permanent roofed constructions that exceed 8.0m² in area (12.0m² in private gardens). Exceptions are made to this area rule for smaller buildings that, due to their detached position, form relatively important topographic features; these are shown at minimum size, as stated above. With a few exceptions (for example, by describing government offices or hypermarkets), no distinction is currently made between residential, private, public, commercial, or industrial buildings.
For Ordnance Survey purposes, antiquities are defined as existing artificial features of a date not later than AD 1714 (the date of the accession of George I). These antiquities are captured along with very important battlefield sites and natural features connected with important historic events. Features and sites of a date later than AD 1714 may be treated as antiquities as an exception if they are of national importance.
The investigation, recording and surveying of archaeology is the responsibility of English Heritage, Historical Environment Scotland (HES) and Cadw (Wales). Antiquity find sites are not shown in OS MasterMap Topography Layer. Ordnance Survey has no responsibility for defining the authenticity of distinctive or descriptive names of antiquities.
A land feature is defined as either a man-made or a natural polygon feature that describes the surface cover and area to which it is applied. This includes both natural and man-made slopes and cliffs. All general features are also placed in the Land theme. There are some exceptions to this, such as routes of communication and buildings.
Rail features are defined as features related to travel by railway or tramway. The exception to this is railway tunnels, which are currently in the Structures theme. OS MasterMap Topography Layer contains information relating to permanent railways that form the network between two points, for example, from railway station to railway station, or from an industrial building to a private quarry.
For Ordnance Survey purposes, a road is defined as a metalled way for vehicles. Roads that form part of the public network and driveways to private properties that are over 100m in length are normally included within OS MasterMap Topography Layer.
A track, for Ordnance Survey purposes, is defined as an unmetalled way that is clearly marked, permanent and used by vehicles. Tracks are only normally recorded in private gardens if they are 100m or more in length. They need not be ‘all weather’. All tracks are described as ‘Track’, or ‘Tk’ if required to be abbreviated. Distinctively named tracks have their name recorded, for example, HICKS LANE (Track).
For Ordnance Survey purposes, a path is defined as any established way other than a road or track. They can be considered as either ‘made’ or ‘unmade’.
Structures are defined as features that are man-made constructions but do not qualify as buildings
(for example, Band Stands and Clock Towers). These features may or may not obstruct passage at ground level. OS MasterMap Topography Layer contains information relating to all permanent structures that are considered large enough to be included.
These are features that denote the ground level at any given point. OS MasterMap Topography Layer does not contain height contours; instead, it contains height information point features of known height.
Water features are defined as features that contain, delimit, or relate to real-world objects containing water.
This section introduces two aspects of deriving additional value from OS MasterMap Topography Layer:
The first aspect is utilising the referencing and change-tracking attributes to identify and manage the impact of change on a user’s data. It discusses the process of applying change and the implications for archiving data.
The second aspect is associating user data and OS MasterMap Topography Layer using the TOID as a common reference. This creates the potential to share data between departments and organisations. It explains what data association is and it gives examples of how data association can bring benefits to organisations.
The feature-reference and change-tracking attributes provide the opportunity for users to put in place a change-management regime. The system that the user uses to translate and load OS MasterMap Topography Layer should use the TOID and version information to update their local holding when a COU is taken onboard.
The software used to manage the holding needs to handle three types of situation: features that have been deleted (known as Deletes), features that are new (known as Inserts), and features that have changed (known as Updates). The software should resolve Deletes as a priority. It is important that COUs are processed with Deletes first, then Inserts and Updates. This is to ensure that updates are applied in the correct order.
In the COU, there is a list of features that have been deleted since the last time the user took data. There are some additional considerations with deleted features, but in essence, the software should find all the TOIDs and versions on the deleted features list in the COU, locate them in the main holding, and remove those features.
In the case of superseded and deleted features, these could be removed totally from the user’s holding, but it may better suit the requirements of the user to archive them for future reference.
With a new feature, called an Insert, the software compares each TOID in the COU against the TOIDs in the existing holding. If the TOID exists in the COU but not in the main holding, it is considered an Insert and the software should put it into the holding.
If the TOID already exists in the holding, the software needs to compare the version number in the existing holding against the version number in the COU. If the version number in the COU is higher than in the existing holding, the software needs to take out the existing version of the feature and replace it with the version contained in the COU. If, on the other hand, the COU version number is lower than the COU version number, the feature should be ignored.
As OS MasterMap features progress through their lifecycles, it is possible to develop snapshots of the features by holding superseded versions in a local data archive. By holding and maintaining a local data archive, users will be able to interrogate previous views of the world straight from their local data holding.
It is important to consider carefully how to archive OS MasterMap Topography Layer features, and what requirements the applications and users will have to access the older information. Archiving may be done by simply writing older versions of the data to hard media, or by a more sophisticated system of keeping historical data live. It is important for users to recognise their own unique requirements (be they user, statutory or regulatory requirements) as archiving can become a significant overhead in terms of storage.
Before designing or implementing an archive of OS MasterMap Topography Layer, it is advisable for a user to discuss requirements with their system supplier.
This getting started guide provides instructions for using OS MasterMap Topography Layer in different software applications. Users with limited technical knowledge will be able to follow this guide.
This getting started guide shows you how to load OS MasterMap Topography Layer into several commonly used geographical information system (GIS) applications.
OS MasterMap Topography Layer is available the following formats:
GeoPackage (area of interest – AOI – only)
Vector tiles (MBTiles)
Geography Markup Language (GML) 2.1.2
The GML download ZIP package contains a GZ (.gz) file, which does not require extraction and contains multiple GML (.gml) files.
The GML data is supplied in 5km2 tiles, but features are not clipped at the tile edges, resulting in what is called “hairy” tiles. All tiles contain six elements:
Cartographic Symbol
Cartographic Text
Boundary Line
Topographic Point
Topographic Line
Topographic Area
OS MasterMap Topygraphy Layer can be downloaded from the OS Data Hub.
OS MasterMap Topygraphy Layer is not available via hard media supply.
This getting started guide focuses on using the product in GML and shapefile format.
For guidance on using the product in GeoPackage or vector tiles formats, please see the following generic getting started guides:
This guide contains instrictions for the following GIS applications:
OS MasterMap Topography Layer data is designed for use as a digital map within GIS and database systems.
For details of Ordnance Survey’s Licensed Partners who can incorporate OS MasterMap Topography Layer in their systems, please see the Our Partners page on the OS website.
Ordnance Survey does not recommend either suppliers or software products. The most appropriate system will depend on many factors, such as the amount of data being taken, resources available within the organisation, the existing and planned information technology infrastructure or, last but by no means least, the applications in which OS MasterMap Topography Layer is to be used.
However, as a minimum, the following elements will be required in any system:
A means of reading the data in its native format, or translating the data into a file format, or storing the data in a database.
A means of storing and distributing the data, perhaps in a database or through a web-based service.
A way of visualising and querying the data, typically a GIS.
There is more information on handling OS MasterMap Topography Layer in product supply.
GeoPackage
Vector tiles (MBTiles)
Geography Markup Language (GML) 2.1.2
Coverage is Great Britain (GB).
File sizes vary greatly depending on tile size and the quantity of features present in a tile:
GeoPackage 25km² tile range: Varies (dependent on AOI selection)
Vector tile GB Supply: Approx. 20GB
GML 25km² tile range: Varies (dependent on AOI selection)
GML GB Supply: Approx. 47GB
OS MasterMap Topography Layer is updated every 6 weeks. Information about the current product version, and information about future and past releases, can be found on the OS MasterMap refresh dates page of the OS website.
Stylesheets are available for OS MasterMap Topography Layer to optimise the cartographic representation of the product, assisting users in visualising and identifying topographic features at a glance. Users can choose the style that suits their use case best from the four different styles available: backdrop, light, outdoor, and standard.
The predefined stylesheets are available in four formats (QML, LYR, SLD and JSON) for interoperability with GIS and web map services. The files can be downloaded via the OS MasterMap Topography Layer Stylesheets page on GitHub.
Click the 'Code' drop-down button and then click 'Download ZIP' on GitHub to access the styling files.
OS MasterMap Topography Layer is grouped into feature themes. Within each theme there will be features deemed to belong to that theme. A feature can belong to more than one theme.
Each feature will have one or more versions of itself which can be tracked as a means of demonstrating change over time. New versions of features will replace existing features through COU, and features that no longer exist can be deleted as a result.
This page introduces the concepts of themes, features, and attributes applicable to OS MasterMap Topography Layer.
A theme is a set of features that have been grouped together for the convenience of users and to provide a high-level means of dividing the data on the layer in a logical and user-friendly fashion. A feature can be a member of any number of themes but must belong to at least one theme as a minimum requirement.
A theme is created by applying rules based on the attributes of features. A theme rule can depend on the common values contained in the feature attributes. A feature is considered a member of each theme to which it passes a theme rule.
Themes are not part of the classification system of features for OS MasterMap. Because of this, a new theme can be created, for the convenience of our users, without in any way affecting either the existing themes or the classification of OS MasterMap features. An overview of each theme for OS MasterMap Topography Layer is given on the product themes page.
In this Overview, the term 'real-world object' is used to describe a geographic entity that can be captured and represented in the data. A real-world object is represented by a feature in OS MasterMap data.
A complete list of the real-world objects and their feature representations is given in the OS MasterMap Real World Object Catalogue, which is available from the Related Links section at the bottom of the OS MasterMap Topography Layer Product Support page on the OS website.
Each feature has one of three geometrical structures – a point, a line, or a polygon. A line feature will have a start and end node that reflects the start and end of the real-world object it represents. Where the start and end node are coincident, the feature created is structured as a polygon. Lines and polygons represent both the location and the geometry of the real-world object. Points do not necessarily represent the exact geometry of the real-world object, just the centroid of its location. Text features are used to provide additional information and context about real-world objects represented by point, line, or polygon features. They are represented as a point, which indicates the location where the text should be displayed.
Polygon features fit with each other topologically within structuring layers. This means that polygons sit adjacent to each other like pieces of a jigsaw puzzle, rather than on top of each other. In the image below, it can be seen that buildings (orange squared-off polygons), if ‘removed’, leaves their footprints in a land feature (green polygon); the land feature does not exist below the buildings.
Each feature comes with an extensive set of attributes that provide information about the feature, for example, its identity, its relationship to other features, its geometry, and the kind of real-world object it purports to represent. Each type of feature has a different set of attributes.
There are two types of attribute information:
Attributes that provide data about the real-world object the feature represents, such as its area or its nature.
Attributes that provide additional information about the feature, such as its lifecycle and quality.
Three of the most important pieces of additional information for the vector layers – the TOID, version, and version date – are discussed in more detail in change management and data association.
OS MasterMap Topography Layer provides attribution that can be searched for and queried within a GIS. Attribution makes it possible to select parcels of land with common features, for example, a polygon attributed as having coniferous tree cover.
This release note provides information about the latest release of OS MasterMap (OSMM) Topography Layer, released to customers on 12 August 2024.
The following table contains product counts for this release of OSMM Topography Layer data. The dates shown are extraction dates, not release dates.
OSMM Topography Layer | Count on 06/06/2024 (Previous release) | Count on 25/07/2024 (Current release) |
---|---|---|
Numerous TOIDs (Topographic Identifiers) have changed since the last refresh, resulting in a visual difference in the data. The list below shows a sample of changed TOIDs and their locations that you can use as 'lookup samples' to validate that your latest supply has updated correctly:
In this release 23 errors were detected of which 2 have existed since the previous refresh. These are all considered to be minor errors and there are no major errors present.
We aim to have all errors resolved prior to the next release as part of ongoing quality improvements.
The next release of OS MasterMap Topography Layer is scheduled for 23 September 2024.
The land cover specification for rural geographies has been refined. The Mountain and Moorland refinement was completed in 2022.
The rural geography updates began capture in May 2022. The initial updates fed through to the July 2022 release of OSMM Topography Layer, with the multi class land cover polygons completed in December 2022. The single class land cover polygons will continue to feed through to product from April 2023.
The following two tables articulate this specification refinement:
The asterisk symbol (*) shows which criteria have been refined.
The land cover specification refinement means that the rural land cover data within OSMM Topography Layer will become more granular, producing a more detailed view made up of smaller more numerous polygons. This provides users with more accurate data that meets each individual’s specific requirements. These changes are purely refinements and do not change the data attribution.
Annex A shows three examples of how the rural land cover refinement is being translated into OSMM Topography Layer.
OS MasterMap Topography Layer was initially developed in response to the need for a national topographic dataset that offers users a more sophisticated type of data that represents the world in a more realistic way and is more aligned to the increasing use and functionality of geographic information systems (GIS) and spatial database technology within organisations.
The product's primary purpose is to provide the most detailed topographic data available of the physical environment of Great Britain. OS MasterMap Topography Layer is regularly updated by ground and aerial survey to a regular schedule, and the data is captured and published to a consistently high standard.
Many users apply geographic products as a starting point to derive their own data, which can be time consuming and inefficient. This is particularly true where features in the data are amalgamations of more than one real-world feature, or even individual parts of a real-world feature. Where the feature represents a real-world feature that has an ‘area’, such as a building or a parcel of land, the feature is represented in the data as a polygon. This should provide opportunities for users to derive their data with greater efficiency and ease as features can be selected either singularly or in groups. The way, and, largely, the extent of a user’s ability to take advantage of the polygonised structure will depend on the systems in use in their organisation. However, most GIS have the necessary ‘data capture’ tools to analyse and interrogate the topography features.
OS MasterMap Topography Layer provides detailed attribution, through its descriptive terms, relating to the real-world object and the group of features it represents. This means certain types of analysis can be performed, without the user having to manually add their own attribution to the data. The themed attribution (see product themes for more information) also means the user can apply their own criteria to refine the data into groups of features that meet their own specific requirements. An example of this would be finding buildings of a certain size by using the calculated area provided as one of the attributes.
It is important for many applications of geographic information (GI) to be able to identify where changes have taken place and the history of a feature's changes. This is important because users may need to learn how the landscape has altered and reflect those changes in their own data. Ordnance Survey updates
OS MasterMap Topography Layer on a regular basis, and these changes are passed on to users through a dataset called change-only update (COU). COU supplies just the features that have changed since the last update or customer user order. This should normally result in much less data needing to be processed and uploaded to the user’s holdings upon the arrival of each update. This is, however, dependent on how frequently the COU data is applied. Furthermore, OS MasterMap Topography Layer is the first product from Ordnance Survey to introduce the concept of feature lifecycles and unique referencing. This makes it possible to relate change in the real world to features in the digital environment, and to identify and manage that change to OS MasterMap Topography Layer so that users can, if they wish, keep their own data holdings up to date. This will also enable the user to assess the consequences of feature changes. It may even be possible, depending on the systems used, for users to roll back their holdings of OS MasterMap Topography Layer to a specific point in time. However, Ordnance Survey does not supply previous versions of any feature or dataset.
One of the most common uses for GI is to produce maps that are coloured to highlight a particular value or property that a real-world feature may have; these are often called thematic maps. An example is given in the image below. This image was created by grouping the calculated area value attribute of each unit on an industrial park into one of five categories. Each category is ‘themed’ with its own colour. The ranges and colours are shown in the legend. Most computer systems offer the ability for features to be assigned a colour or style based on the value of an attribute; OS MasterMap Topography Layer has both the structure and attribution to make it relatively quick to produce such thematic maps. The result is data that is easier to customise, easier to interpret and more eye-catching.
One common barrier to users is linking datasets together and sharing this data with other Ordnance Survey users, making greater use of their own data. To be able to link or ‘associate’ datasets together normally requires each dataset to have a common reference – one piece of information that is in all datasets. OS MasterMap Topography Layer can help to create links between users’ own datasets and
OS MasterMap features by using the TOID as a common reference. In this way, OS MasterMap Topography Layer provides a foundation dataset for a Digital National Framework that aims to help users of spatial data to derive more value by associating datasets together. Using a common reference can also provide such benefits to an organisation as removing ambiguity over a feature’s identity and allowing the faster retrieval of data when querying or analysing the data.
This release note provides information about the latest release of OS MasterMap (OSMM) Topography Layer, released to customers on 24 June 2024.
The following table contains product counts for this release of OSMM Topography Layer data. The dates shown are extraction dates, not release dates.
OSMM Topography Layer | Count on 25/04/2024 (Previous release) | Count on 06/06/2024 (Current release) |
---|---|---|
Numerous TOIDs (Topographic Identifiers) have changed since the last refresh, resulting in a visual difference in the data. The list below shows a sample of changed TOIDs and their locations that you can use as 'lookup samples' to validate that your latest supply has updated correctly:
In this release 5 minor errors were detected, of which 2 have existed since the previous refresh. All errors detected are considered to be minor. We aim to have all 5 errors resolved prior to the next release as part of ongoing quality improvements.
The next release of OS MasterMap Topography Layer is scheduled for 12 August 2024.
The land cover specification for rural geographies has been refined. The Mountain and Moorland refinement was completed in 2022.
The rural geography updates began capture in May 2022. The initial updates fed through to the July 2022 release of OSMM Topography Layer, with the multi class land cover polygons completed in December 2022. The single class land cover polygons will continue to feed through to product from April 2023.
The following two tables articulate this specification refinement:
The asterisk symbol (*) shows which criteria have been refined.
The land cover specification refinement means that the rural land cover data within OSMM Topography Layer will become more granular, producing a more detailed view made up of smaller, more numerous polygons. This provides users with more accurate data that meets each individual’s specific requirements. These changes are purely refinements and do not change the data attribution.
Annex A shows three examples of how the rural land cover refinement is being translated into OSMM Topography Layer.
The following instructions are based on ArcGIS Pro version 2.8.1 and assume that you have access to and knowledge of the UK Data Loader and the Data Interoperability Extension to convert the supplied GML into a suitable ArcGIS Pro format.
if you do not have access to the UK Data Loader and the Quick Import (Data Interoperability) extension, use the translation tools available in FME or QGIS to convert the GML data to shapefiles, or import it into an ESRI Geodatabase before loading them into ArcGIS Pro.
The UK Data Loader is an ArcGIS toolbox. It contains a set of tools that primarily allow loading of Ordnance Survey data into an ArcGIS workspace.
If the UK Data Loader is not already installed, we recommend you add the folder containing the toolbox into your documents. More information on installing the UK Data Loader is available in ESRI’s . This guide also provides instructions for processing Change Only Updates (COU) for OSMM Topography Layer.
Using the UK Data Loader involves two steps: Converting the GML supply and loading the converted file geodatabase into ArcGIS Pro.
Before you start, you need either an existing file geodatabase (.gdb) or a database connection to load the files into.
To load the GML data into ArcGIS Pro using the UK Data Loader:
Open an existing project or create a new one.
You may want to select a basemap for backdrop context.
From the View tab, select Catalog View.
In the Catalog view, navigate to the location in which your UK Data Loader toolbox is saved.
You may need to connect to the relevant folder using the Add Folder option in the Insert tab.
Open the toolbox, navigate to OS MasterMap Topography Layer > Load OSMM Topography Data, right- click on the script, and click Open in the context menu.
This will open the Geoprocessing panel in which you can set the parameters for running the script:
Source Data Folder: Navigate to and select the GML file(s) required.
Existing Destination Workspace: Navigate to and select the pre-existing file geodatabase (.gdb) folder to load the data into.
Logging File Folder: Navigate to and select a folder into which to save the log that will be created during data processing. This is important because any error messages will be captured here. These may help identify issues.
Feature Class / Table Prefix: Enter a prefix for your tables (for example, Topo_).
Create Annotation Line Features: Check this option if it is available and required. This checkbox option is only available in older versions of ArcGIS Pro/UK Data Loader.
This may take some time, depending on the number of 5km OSMM Topography Layer tiles being processed.
On completion, the OSMM Topography Layer data will be saved to the destination file geodatabase, which can then be loaded into the workspace by following the instructions in the next section.
Having converted your GML data to file geodatabase using the UK Data Loader (or other tools listed in this guide), you can now load the OSMM Topography Layer GDB into your ArcGIS Pro workspace.
To load and display the file geodatabase in an ArcGIS Pro workspace:
Open an existing project or create a new one.
You may want to select a basemap for backdrop context.
From the Map tab, select Add Data.
In the Add Data dialog, navigate to and select the file geodatabase (.gdb) containing the OSMM Topography Layer data, and then click OK.
In the selected file geodatabase (.gdb) select the feature classes that you want to load and then click OK.
You can select multiple feature classes at once to save repeating these steps for all the OSMM Topographic Layer features.
Your OSMM Topography Layer feature classes will now appear in both the Contents panel and map area.
You may need to reorder the layers to see the data correctly. You can reorder layers using drag and drop. We recommend the following layer order: CartographicText, CartographicSymbol, TopographicPoint, BoundaryLine, TopographicLine and TopographicArea.
As an alternative to using the UK Data Loader, you can load OSMM Topography Layer shapefiles directly into your ArcGIS Pro workspace. You need to first convert your GML data to shapefile.
Translation tools available in FME and QGIS to convert the GML data to shapefiles.
To load and display shapefiles in an ArcGIS Pro workspace:
Open an existing project or create a new one.
You may want to select a basemap for backdrop context.
From the Map tab, select Add Data.
In the Add Data window, navigate to and select the shapefiles (.shp) containing the OSMM Topography Layer data, and then click OK.
You can select multiple shapefiles at once to save repeating these steps for all the OSMM Topographic Layer features.
Your OSMM Topography Layer shapefiles will now display in both the Contents panel and map area.
You may need to reorder the layers to see the data correctly. You can reorder layers using drag and drop. We recommend the following layer order: CartographicText, CartographicSymbol, TopographicPoint, BoundaryLine, TopographicLine and TopographicArea.
These instructions are based on QGIS version 3.22.4 and assume you have set the default coordinate reference system to British National Grid (EPSG 27700).
There are two ways to load the GML supply into QGIS: You can use drag and drop or the Data Source Manager.
To load the GML supply using drag and drop:
Open an existing QGIS project or create a new one.
In the file system on your computer system (for example, in Windows Explorer), select the GML data (.gz file).
Drag and drop the file directly into the QGIS UI.
In the Select Items to Add dialog:
If you use multiple screens, this dialog may open on another screen.
Select each required layer or click Select All to select all layers.
Check the Add layers to a group option.
This groups the layers by OSMM Topography Layer tile reference.
Click Add Layers.
The GML data will now display in both the Layers panel and the map area.
To load the GML supply into QGIS using Data Source Manager:
Open an existing project or create a new one.
In the Layer menu, click Data Source Manager.
In the Data Source Manager dialog:
Select Vector from the data menu on the left.
In Source > Vector Dataset(s), click ‘…’, navigate to and select the GML on your computer.
Click Add.
In the Select Items to Add dialog:
If you use multiple screens, this dialog may open on another screen.
Select each required layer or click Select All to select all layers.
Check the Add layers to a group option.
This groups the layers by OSMM Topography Layer tile reference.
Click Add Layers.
The data will now display in both the Layers panel and the map area.
Data is typically grouped by tile reference in the Layers panel. If you open two or more OSMM Topography Layer layers simultaneously (for example, TopographicArea and BoundaryLine), you may need to reorder the layers to see the data correctly.
You can reorder layers using drag and drop. We recommend the following layer order: CartographicText, CartographicSymbol, TopographicPoint, BoundaryLine, TopographicLine and TopographicArea.
Using GML data in QGIS is not always the best option. You should consider converting your data to another format (for example, shapefile) for the following reasons:
When working with multiple tiles of 5km2 OSMM Topography Layer data, GML data does not always merge seamlessly.
Rendering performance of GML data in QGIS is not as good as other formats, because GML data cannot be spatially indexed.
The sections that follow show you how to convert GML data to shapefile and how to apply a spatial index to shapefiles.
To convert GML to shapefile in QGIS:
In the Layers panel, right-click on the layer you want to convert and click Export > Save Features As....
In the Save Vector Layer as… dialog:
Format: Select ESRI Shapefile.
File name: Click …, navigate to the folder in which you want to store the shapefile, name the file, and click Save.
Check the Add saved file to map option.
Click OK.
You can watch the export progress in the blue progress bar at the bottom of the QGIS UI. When the process is complete, the shapefile layers will display in the Layers panel and the map area.
Repeat steps 1 - 2 above for each layer (for example, TopographicLine, CartographicText…) that you want to convert.
When working with shapefiles, we recommend you apply a spatial index to the data, particularly when loading large or national sets of data. This significantly improves performance when rendering and panning the data.
To apply a spatial index to a shapefile in QGIS:
In the Layers panel, right-click on the shapefile layer you want to index and click Properties in the context menu.
In the Layer Properties dialog:
Select Source in the navigation menu on the left.
In Geometry click Create Spatial Index.
Click OK to close the confirmation dialog.
Click Apply and then OK.
Your shapefile layer will now be spatially indexed; this improves rendering and querying performance.
Repeat steps 1 and 2 above for each layer you want to create an index for (for example, TopographicLine, CartographicText…).
There are several options available to customers when ordering data in GML format that provide additional metadata or aid data management.
To make the management of large areas easier, data is split into chunks, each of which covers a nominal square area. Data can also be supplied as part of a squared area to complete a predefined area as part of a nominated file size. Two types of chunks are available: geographic and non-geographic chunks. Chunk boundaries are imposed purely for the purpose of dividing large supply areas into pieces of manageable size in a geographically meaningful way. Both Full Supply and updates (whether COU or Full Resupply) are chunked.
As OS MasterMap Topography Layer data is seamless, GML files containing large areas could be very data intensive. In order to provide files of a manageable size, data supplies are divided into chunks of user-specified size, each of which is supplied in a separate GML file. The figure below illustrates how geographic chunks work:
The process of chunking has the following steps:
The user submits an AOI by either drawing an AOI or uploading a pre-defined AOI to the OS Data Hub platform (or OS Orders).
Both online ordering systems create a grid covering the entire area based on the user-specified size (for example, 25km²).
Each square within the grid forms a chunk file.
Each feature that intersects that square goes into the chunk file.
National (GB) cover of OS MasterMap Topography Layer in GML format is supplied in 25km² chunks.
In the case shown in the image above, 10 chunks have been created. The central chunk is a complete grid square; the other chunks are partly bounded by the data selection polygon. The upper-left square shows the effect when the data selection polygon crosses a grid square twice – i.e. two or more separate chunks are created.
A consequence of chunking is that some features are supplied in more than one chunk. Systems reading OS MasterMap Topography Layer data must identify and provide the option to remove these duplicated features.
If a chunk contains no information relating to a user’s selected themes, then it is not supplied.
Chunks cannot be treated as persistent data management units; as it is a floating grid, the origin of the chunking grid may differ between orders, particularly if the contract area changes or if a different chunk size is ordered.
The packaging of a seamless dataset into chunks means that where a feature lies across or touches the boundary of several chunks, it is supplied in all the related chunks. This is because an individual feature is the smallest unit within the OS MasterMap Topography Layer, and it cannot be physically split into two or more parts.
When a polygon falls across a chunk edge, but its bounding line(s) lie outside, it may not be included in that chunk. It will be included in the adjacent chunk, unless the polygon is at the edge of the contract area, in which case, the line will not be supplied at all.
When a polygon changes so that it no longer falls in the same chunk, for instance, when an OS MasterMap Topography Layer feature used to lie partly inside a chunk and instead is now reduced in size so it is wholly within an adjacent chunk, it is reported as a deleted feature (a Delete) in one chunk and as a modified feature (new version, known as an Update) in the adjacent chunk. This is shown in the diagram below.
It is possible for OS MasterMap Topography Layer features with point geometry to be included in multiple adjacent chunk files. This is because the query used to populate a chunk file includes all features that touch its boundary, and this boundary is shared with adjacent chunks. Therefore, loading software must be able to identify and remove duplicate point features across multiple files in the same way as features represented by lines and polygon geometries.
This supply format delivers the files in a fixed nominal size, as opposed to a given geographic area depending on user preference.
Unlike in geographic chunking, each feature in non-geographic chunking appears in only one chunk file. It is possible for features from various geographic locations to appear in a single file, and for adjacent features to appear in different files. Non-geographic chunk files are designed for use as a set to load spatial databases but can be used in a file format if all chunks are translated or imported into the system at the same time.
It is not possible to tell in which file a particular feature will be found before reading the files. With non-geographic chunks, there are no duplicate features lying across chunk edges; this speeds up the translation process.
The features shown in red below can end up in the same non-geographic chunk even though they are not adjacent to each other.
The Feature Validation Dataset (FVDS) is a set of files that can optionally be supplied with either a Full Supply COU or an AOI COU of an OS MasterMap Topography Layer order in GML format. The FVDS allows a user to validate that the data holding contains the correct set of features after loading. It does this by reporting on all the data it expects to find in the holding after the application of the supply, not just what is contained in the supply.
The FVDS is intended to be used for periodic checks on data holdings maintained by a COU regime. It is not necessary for users to order it with every supply, as processing it will slow the translating process. It can also be used to check that an initial supply of OS MasterMap Topography Layer data has been correctly loaded. The FVDS can be used with both geographic and non-geographic chunk file options.
The FVDS is itself divided into files on a non-geographic basis, using a 10MB nominal file size.
The FVDS is a comma-separated value (.csv) text file format that gives the TOID, version number and version date of every feature that should exist in the current data holding, based on the polygon extent,
themes, polygon format and extraction date of the current order. Each .csv file is compressed to a .gz file using the same compression algorithm used for OS MasterMap Topography Layer GML files.
An order summary file in GML format will be supplied with all OS MasterMap Topography Layer orders, containing the order information specified by the user. This information includes:
The order number
Query extent polygon(s) of the order
The order type: Full Supply or COU (for COU orders, the change since date will be included)
The themes requested
The chunk type: Non-geographic or geographic
The chunk size (in MB for non-geographic chunks; in km² for geographic chunks)
OS MasterMap Topography Layer incorporates a web-based ordering system that allows users to order their initial data supply and any updates, obtain price estimates and view details of their holdings on demand. The product is supplied as an online download. You can download data in its various formats from the .
Please note that some formats are only available via , Ordnance Survey's legacy ordering system; these formats are indicated in the following table:
Formats | AOI Supply | AOI Supply | GB Supply | GB Supply |
---|
* Feature Validation Dataset (FVDS) and Change-Only Update (COU) available.
† Only available via OS Orders.
Full GB coverage of OS MasterMap Topography Layer in GeoPackage format as a single AOI will be too large for the majority of GIS to handle.
There are two main supply options available for OS MasterMap Topography Layer: Full Supply or COU.
Initial Supply refers to the first order of OS MasterMap Topography Layer that a user makes, which will contain all features for all the layers selected for the area covered by the order. Upon Initial Supply, users can select whether they would like to receive future data updates as COU (user receives only the tiles/features that have changed since the last update) or a Full Supply (user receives all tiles/features regardless of whether they have changed since the last product update). COU data contains new and updated versions of features (known as Inserts and Updates, respectively), and information about departed features (known as Deletes); any feature within the area covered by the order that has not undergone any change will not be supplied.
The advantage of taking a COU Supply rather than a Full Supply is that, if applied regularly, the amount of data that must be processed and loaded is much smaller with a COU Supply. Users may request updates of the latest changes in their AOI, at any time, using the online service. Updates can either be for specified AOIs or GB wide.
It is advisable to apply COU updates for all the OS MasterMap layers to which you have subscribed at the same time to ensure cross-product synchronicity. OS MasterMap layers include the following products:
OS MasterMap Topography Layer, OS MasterMap Sites Layer, OS MasterMap Building Height Attribute,
OS MasterMap Greenspace Layer, OS MasterMap Highways Network – Roads, OS MasterMap Highways Network – Routing and Asset Management Information (RAMI), OS MasterMap Highways Network – Paths, and
OS MasterMap Water Network Layer.
These instructions are based on Cadcorp SIS Desktop Express 9.0.2511 and assume you have set the default coordinate reference system to British National Grid (EPSG 27700). These instructions also work for the fully licenced version of Cadcorp SIS Desktop.
There are two ways to load the GML supply into Cadcorp SIS Desktop: You can use drag and drop or add and overlay.
To load and display the GML supply using drag and drop:
Open an existing project or create a new one.
In the file system on your computer system (for example, in Windows Explorer), select the GML data (.gz file).
Drag and drop the file directly into the Map area in Cadcorp SIS Desktop.
Data processing will begin automatically. You can monitor the progress by watching the spinning blue circle in the bottom left of the UI.
When processing is complete, the data will display in the Maps panel and Map area.
Cadcorp produces their own OS MasterMap Topography styling, which automatically styles your OMMM Topography data. If you cannot see your data, zoom to > 1:4,000 scale and it should become visible.
To load and display the GML supply by adding an overlay:
Open an existing project or create a new one.
From the Home tab, click Add Overlay.
In the Overlay Types dialog:
Click Files in the left navigation menu.
Click File in the options on the right.
Click Next>.
In the File Browser dialog:
Navigate to and select the GML data (.gz file) you want to load.
Click Finish.
Data processing will begin automatically. You can monitor the progress by watching the spinning blue circle in the bottom left of the UI.
When processing is complete, the data will display in the Maps panel and Map area.
Cadcorp produces their own OS MasterMap Topography styling, which automatically styles your OMMM Topography data. If you cannot see your data, zoom to > 1:4,000 scale and it should become visible.
The underlying database for OS MasterMap Topography Layer is live and undergoes continuous revision. When a user orders COU, a ‘change since’ date is specified, and all features that have changed since midnight on the date specified are supplied. This will normally be the date the data was last extracted from the Ordnance Survey main database but could be a previous date. The last extraction date can be found on the along with the update history and release notes for the product.
To be able to resolve changes to the data holding, the system used to translate or load the data must check the TOID and version of every feature in the update against the current data holding to determine whether it should be loaded, and if so, what existing feature(s) it replaces. This makes it possible to request and load COU with a date preceding the last data supply date without damaging the data holding. This process can be used to correct a data holding if inconsistencies have occurred due to partially loaded or non-sequential COU, by ordering a single COU with a change since date that precedes the problem updates.
For users taking a Full Great Britain (GB) Supply of OS MasterMap Topography Layer, there is a Managed Great Britain Sets (MGBS) service. The MGBS service is available for GML or vector tiles formats only (full GB coverage of OS MasterMap Topography Layer in GeoPackage format as a single AOI will be too large for the majority of GIS to handle).
OS Data Hub users will be automatically notified (via email) when their Full Supply or COU MGBS is available from their 'Data Package' area on the OS Data Hub, in accordance with product refresh dates as stated on the .
OS Orders users will automatically receive their updates (Full Supply or COU) on DVD or hard drive, either quarterly or every six weeks (whichever option was selected at initial order).
MGBS users and Ordnance Survey Licensed Partners that take GB coverage can benefit from:
Data arriving faster and in a more predictable and timely manner
Seeing the same version of features as other organisations
Easier data management
A Feature Validation Dataset (FVDS) with all COU orders or with Full Supplies on request (GML format only)
These instructions are based on MapInfo Professional 2019 and assume you have set the default coordinate reference system to British National Grid (EPSG 27700).
While MapInfo Professional can open GML files without prior translation, for performance and compatibility reasons, we recommended you use the Universal Translator built into MapInfo Professional versions 12.5 onwards to convert the GML supply to MapInfo TAB files prior to loading the data.
The sections below provide instructions for both working with GML data and converting to MapInfo TAB.
To load and display the GML supply directly in MapInfo Professional:
Open an existing workspace or create a new one.
From the Home tab, click Open > Universal Data.
In the Specify Data Source dialog:
Format: Select GML (Geography Markup Language).
Dataset: Click …, and navigate to and select the GML file (.gz) in the file browser.
Click OK.
In the Select Layers dialog, select the layers you want to load and click OK.
Your GML data will now display in the Maps panel and map area.
To convert the GML supply to MapInfo TAB in MapInfo Professional:
Open an existing workspace or create a new one.
In the Home tab, click Open > Universal Data.
In FME Quick Translator, click Translate.
In the Set Translation Parameter dialog:
Reader Format: Select GML (Geography Markup Language).
Reader Dataset: Click …, and navigate to and select the GML file in the file browser.
Format: Select MapInfo TAB (MAPINFO).
Dataset: Click …, and navigate to and select the folder you want the translated data saved to.
Click OK.
You can watch the translation progress log in the FME Quick Translator. It will take some time; a single 5km tile of OSMM Topography Layer in GML format takes approximately 30 seconds. When the process is complete, a message similar to the example below will display.
You can now close the FME Quick Translator.
You can now load the translated data into MapInfo Professional as TAB format using the instructions provided in the following section.
If translating multiple tiles of OSMM Topography Layer using the above method, the files will be automatically appended into a single table, avoiding the need to merge tables. However, duplicate features are not removed automatically. See Deleting duplicate entries from tables for guidance on how to handle this.
To load the converted MapInfo TAB files in MapInfo Professional:
Open an existing workspace or create a new one.
From the Home tab click Open > Table.
In the file browser:
Files of type: Select MapInfo (*.tab).
Navigate to the folder in which you stored the converted MapInfo TAB files and select the layers you want to open.
Click Open.
Your MapInfo TAB data (.tab) will now display in the Maps panel and map window.
In MapInfo Professional it is possible to merge the elements of two TAB files into one new table using the append function.
Appending only works for data tables of the same type AND for two TAB files at a time. Because OS MasterMap Topography Layer data comprises six individual tables, we recommended that you merge two or more tiles during the conversion from GML to TAB process.
To merge two TAB tables:
Follow the steps in Converting GML to MapInfo TAB above for both files.
Select one of your tables in the Explorer panel.
In the Home tab click Append Rows.
In the Append Rows to Table dialog:
Append Table: Select the table that will be appended.
to Table: Select the table to append to
Click OK.
The data from one table will now have been appended into the other. You will need to save the table to retain the appended data. See below for instructions on how to do this.
To verify which table contains the appended data:
Right-click a table in the explorer and click Browse Table in the context menu.
The total number of rows in the table displays in the bottom bar; this value of will be considerably larger for the table that included the appended rows.
To save the table:
Select the table containing the appended rows in the explorer.
From the Table tab click Save > Save Table.
As an alternative, you can use the Save Copy As action to additionally retain the original, unmerged table.
In the Save Table confirmation dialog click Save to confirm your action.
Your table will now contain the data for both original TAB files; you can verify this by opening the table to check the contents.
There are several ways to delete duplicate entries from tables MapInfo Professional. Please refer to the MapInfo Professional documentation for guidance:
TOID | Location (i.e. XY coordinates) |
---|---|
Geographic area | Minimum area size for land cover | Minimum width |
---|---|---|
Geographic area | Minimum area size for land cover | Minimum width |
---|---|---|
TOID | Location (i.e. XY coordinates) |
---|---|
Click (Run button) at the bottom of the panel to process the data.
The data is un-styled. See documents for guidance on styling OSMM Topography Layer data.
The data is un-styled. See documents for guidance on styling OSMM Topography Layer data.
While the files are now merged, duplicate features (resulting from “hairy tiles”) are not removed automatically. See from tables for guidance on how to handle this.
This article describes how to use SQL queries.
Search for the Delete Duplicates Tool.
Total Feature Count
508 882 836
509 529 397
Count of Topo Area
127 289 166
127 455 397
Count of Topo Line
350 655 720
351 126 174
Count of Topo Point
4 388 037
4 388 827
Count of Topo Bline
531 327
530 617
Count of Topo CartoSym
3 789 871
3 788 942
Count of Topo CartoTxt
22 228 715
22 239 440
Total Count of Deletes
602 375
636 733
Count of Topo Area deletions
119 554
129 723
Count of Topo Line deletions
449 655
478 982
Count of Topo Point deletions
2 553
2 227
Count of Topo Bline deletions
1 350
1 374
Count of Topo CartoSymcc deletions
4 460
4 265
Count of Topo CartoTxtcc deletions
24 803
20 162
Total Count of Inserts
1 156 041
1 283 294
Count of Topo Area inserts
262 381
295 954
Count of Topo Line inserts
852 128
949 436
Count of Topo Point inserts
4 869
3 017
Count of Topo Bline inserts
420
664
Count of Topo CartoSym inserts
5 489
3 336
Count of Topo CartoTxt inserts
30 754
30 887
Total Count of Modifications
1 181 874
1 213 405
Count of Topo Area Modifications
601 058
611 739
Count of Topo Line Modifications
563 973
585 817
Count of Topo Point Modifications
220
256
Count of Topo Bline Modifications
2 947
1 485
Count of Topo CartoSym Modifications
46
51
Count of Topo CartoTxt Modifications
13 630
14 057
COU Size (bytes)
507 742 477
539 082 200
osgb5000005333761759
266379.141, 661146.076
osgb1000002102169148
330922.334, 436520.256
osgb1000001792521555
514257.13, 177195.224
osgb1000000390862765
181610.432, 697265.48
osgb1000002031686162
377705.95, 414622.45
osgb5000005127065768
563861.53, 189432.44
Urban
0.1hectares (ha) (1 000m²)
5m
Rural
0.1hectares (ha) (1 000m²)
10m
Mountain and moorland
1.0hectares (ha) (10 000m²)
10m
Urban
0.1hectares (ha) (1 000m²)
5m
Rural
0.1hectares (ha) (1 000m²)
5m*
Mountain and moorland
0.1hectares (ha) (1 000m²)*
5m*
Total Feature Count
508 329 170
508 882 836
Count of Topo Area
127 146 339
127 289 166
Count of Topo Line
350 253 247
350 655 720
Count of Topo Point
4 385 721
4 388 037
Count of Topo Bline
532 257
531 327
Count of Topo CartoSym
3 788 842
3 789 871
Count of Topo CartoTxt
22 222 764
22 228 715
Total Count of Deletes
387 625
602 375
Count of Topo Area deletions
78 038
119 554
Count of Topo Line deletions
277 326
449 655
Count of Topo Point deletions
3 039
2 553
Count of Topo Bline deletions
533
1 350
Count of Topo CartoSymcc deletions
6 393
4 460
Count of Topo CartoTxtcc deletions
22 296
24 803
Total Count of Inserts
837 247
1 156 041
Count of Topo Area inserts
189 219
262 381
Count of Topo Line inserts
587 842
852 128
Count of Topo Point inserts
13 345
4 869
Count of Topo Bline inserts
218
420
Count of Topo CartoSym inserts
17 235
5 489
Count of Topo CartoTxt inserts
29 388
30 754
Total Count of Modifications
736 646
1 181 874
Count of Topo Area Modifications
369 267
601 058
Count of Topo Line Modifications
353 690
563 973
Count of Topo Point Modifications
231
220
Count of Topo Bline Modifications
2 681
2 947
Count of Topo CartoSym Modifications
44
46
Count of Topo CartoTxt Modifications
10 733
13 630
COU Size (bytes)
333 062 363
507 742 477
osgb1000000828071143
283459.15, 558287.03
osgb1000032166978
420041.3, 420633.65
osgb1000002023902176
570547.2, 321617.6
osgb1000000051338601
400106.45, 867491.455
osgb5000005222007891
334818.55, 415223.62
osgb1000001792732699
516068.135, 172721.936
Geographic area
Minimum area size for land cover
Minimum width
Urban
0.1hectares (ha) (1 000m²)
5m
Rural
0.1hectares (ha) (1 000m²)
10m
Mountain and moorland
1.0hectares (ha) (10 000m²)
10m
Geographic area
Minimum area size for land cover
Minimum width
Urban
0.1hectares (ha) (1 000m²)
5m
Rural
0.1hectares (ha) (1 000m²)
5m*
Mountain and moorland
0.1hectares (ha) (1 000m²)*
5m*
Geographic chunks | Non- geographic chunks | Geographic chunks | Non- geographic chunks |
GeoPackage | Six files (one file per feature type) | Six files (one file per feature type) | N/A | N/A |
Vector tiles | N/A | N/A | Six files (one file per feature type) | Six files (one file per feature type) |
GML | 2km² tiles*† | 10MB files*† | 5km² tiles | 30MB files |
GML | 5km² tiles* | 30MB files* | 5km² tiles | 30MB files |
GML | 10km² tiles*† | 50MB files*† | 5km² tiles | 30MB files |
This section is an addendum to cartographic style definitions, containing guides to applying tables for Topography Layer features hat have been enriched with additional descriptive terms. Only features with new descriptive terms have been provided.
You can use the Astun Technology Loader to convert GML 2.1.2 data to other geospatial and non- geospatial formats.
This is a free, open-source loader for geographic data in GML and KML formats. It is written in Python and uses OGR 1.9. source data to output to any format supported by OGR, for example, shapefile and MapInfo TAB.
The loader was last updated in September 2022. Installation files and guides for the loader, including configuration examples, are available from the AstunTechnology/Loader GitHub repository.
To overcome the challenges posed by multiple styling methods and to ensure that users get the most out of the detailed content available, Ordnance Survey developed a post-processing method to create a new discrete style attribute that can be used to style OS MasterMap Topography Layer.
We created a key attribute, “style_code”, which is populated with integers that correspond to a style for a given feature. This code is based on logic similar to the process described in our Standard Styling Specification, but with far fewer unique feature styles. We chose to use integers, rather than text, to improve system performance during processing. The use of integers, together with a text description, makes the new styling easy to understand and apply.
Styling information, SQL scripts, stylesheets and related resources are available from the Ordnance Survey OSMM-Topography-Layer-stylesheets GitHub repository.
To support the wide variety of OS MasterMap users, the provided resources include:
Stylesheets: In SLD (Geoserver), LYR (ESRI Layer), LYRX (ArcGIS Pro), QML (QGIS) formats in a backdrop style, and Mapbox GL styles.
SQL database scripts: For Oracle, PostgreSQL/PostGIS and SQL Server to post process your database.
Symbology fonts: OSMasterMap TrueType font and SVG images.
FME: Transformer(s) for FME Workbench.
QGIS-Field Calculator: Text files and instructions on how to use the QGIS field calculator to add styling attribution.
To create the post-processing styling method, we followed these steps:
Queried the OS MasterMap Topography Layer database to create a list of discrete features grouped by combinations of descriptiveGroup, descriptiveTerm, make and physicalPresence. The results were ordered by total count.
Added a styling description for each combination.
This was done by the Cartographic Design team who considered whether each discrete feature should have its own style rule or whether it could be styled like a similar feature.
Added a numerical styling code.
This was based on previous feedback from users who had used the “os_cat” styling method. Using numbers has
important performance benefits; a stylesheet looking to match data with “Building Outline Line” is significantly slower than one matching with an integer value of “2”, for example.
Wrote SQL database scripts that post processes the database tables to add the new styling attributes, and stylesheets that look for the new style code attribute.
The attribute tables section contains tables that list the attributes used to create the new style rules for each OS MasterMap Topography Layer type.
OS MasterMap Topography Layer contains features that represent objects in the physical environment, such as buildings, fields, fences, and letter boxes. It also includes intangible objects, such as county boundaries and the lines of mean high or low waters. There are over 500 million features in the product.
Ordnance Survey has developed a post-processing styling method that creates a cartographic styling utilizing discrete style attributes (style_code, colour_code, font_code and more) to ensure that users get the most out of the rich content available OS MasterMap Topography Layer. This guide describes this styling method and the related resources provided by Ordnance Survey, and shows you how to use the resources in various geographical information systems (GIS).
A number of methods have been developed to style OS MasterMap Topography Layer over time:
featurecode: This is the easiest method, but it provides only a limited number of styles and can result in mis-styled features when the same featurecode is used for multiple feature types.
featurecode and make: This method makes it possible to distinguish between features that share the same featurecode but have different values for ‘make’. A good example of this is Rail:
featurecode = 10167 AND make = ‘Manmade’
featurecode = 10167 AND make = ‘Natural’
This method is used in the open source stylesheets on the QGIS-UK/Styles GitHub repository.
descriptiveGroup, descriptiveTerm and make: How to use these three descriptive attributes is outlined in the OSMM Topography Layer - Standard Styling Specification.
descriptiveGroup, descriptiveTerm, make and physicalPresence: Using these four descriptive attributes provides access to the richness of the OS MasterMap Topography Layer data but is the most difficult method to implement.
Custom style attribute: A few Partners have implemented the creation of a new style attribute during the loading/processing of OS MasterMap Topography Layer. This gives features a discrete attribute on which to style that is far more efficient.
OS discrete styling attribute: Several years ago, we released Styled Layer Descriptors (SLDs) for OS MasterMap Topography Layer that used a discrete style attribute called os_cat. This attribute is a textual description (for example, buildingFill) that is created by post processing the data.
Multiple available styling methods made it difficult to provide uniform guidance for OS MasterMap Topography Layer, because the stylesheets look for a particular attribute field, which may not exist in the translated data. For example, descriptiveGroup can become descgroup or desc_group or DESCRIPTIVEGROUP.
The following resources provide additional information about the concepts in this guide:
Oracle INSTR Function - https://docs.oracle.com/cd/B28359_01/olap.111/b28126/dml_functions_1103.htm#OLADM564
PostgreSQL MVCC - http://www.postgresql.org/docs/current/static/mvcc-intro.html
PostgreSQL Pattern Matching - http://www.postgresql.org/docs/9.4/static/functions-matching.html
PostgreSQL Array Operators - http://www.postgresql.org/docs/9.4/static/functions-array.html
OGC Style Layer Descriptor - http://www.opengeospatial.org/standards/sld
The stylesheets are available in the Stylesheets directory of the Ordnance Survey OSMM-Topography-Layer- stylesheets GitHub repository.
You can either fork the stylesheets from the GitHub repository or download the repository and extract the files.
Four different types of stylesheets are provided (SLD, LYR, LYRX and QML) to help users apply the styles in as many applications as possible. Each stylesheet type is discussed in a separate section below.
A Mapbox style is a document that defines the visual appearance of a map: what data to draw, the order to draw it in, and how to style the data when drawing it. A style document is a JSON object with specific root level and nested properties. This specification defines and describes these properties.
The Mapbox GL styles (.json) for OS MasterMap Topography Layer Vector Tiles are for use in Mapbox Studio, Maputnik and other compatible software.
They have been designed to work with the data as it is supplied.
The fonts and sprites required for each style are supplied for if you want to use the styles offline/locally. You will need to host these locally and input the host locations into the .json file where prompted.
This section contains instructions on how to use the scripts in various databases (PostgreSQL/PostGIS, Oracle and SQL Server) and an overview of the key principles on which the scripts are based.
The SQL scripts are available in the SQL directory of the Ordnance Survey OSMM-Topography-Layer- stylesheets GitHub repository.
Before using the SQL scripts, you need to determine how your OS MasterMap Topography Layer loading software handles the descriptiveGroup and descriptiveTerm attributes, because these attributes often contain multiple values. Some loaders use a simple VARCHAR(254) data type and load in the data as a comma separated list of values, while others load in the data as an array. For example, this is what a descriptiveTerm with multiple values, looks like when loading OS MasterMap Topography Layer data using:
FME: Rough Grassland,Scrub,Heath
GDAL/OGR2OGR library: {“Rough Grassland”,Scrub,Heath}
This is an important distinction as it determines which SQL queries you can use to find the different descriptiveGroup and descriptiveTerm values. If you are unsure which method your loader uses, look at the data in your database or at the CREATE TABLE SQL statement that was used. Either of these will show you the data type of each attribute field. For example, in PostgreSQL/PostGIS using OGR2OGR, if the descriptive term field was created as descriptiveterm character varying[], it is an ARRAY. When you know this, you can choose the correct SQL query script to use.
Before running the SQL scripts, please check your schema and table names as these may be different from those used in our SQL queries. You can use find and replace in a text editor to tweak the SQL queries to match your database configuration.
These instructions are based on FME Desktop 2022.1.1.
To load and display the GML supply in FME Desktop 2022.1.1.
Open an existing workspace or create a new one.
From the Reader tab click Add Reader…
In the Add Reader dialog:
Format: Select OGC GML (Geography Markup Language).
Dataset: Click …, and navigate to and select the GML file (.gz) in the file browser.
Coord. System: Select ESPG: 27700 (British National Grid).
Click OK.
In the Select Feature Types dialog select the required layers and click OK.
This dialog may take a while to load. You can watch the progress in the green bar at the bottom left of the FME window.
Figure 53:FME Desktop Select Feature Types dialog
When processing is complete, your features will appear as readers in the FME workspace.
Right-click one of the feature readers and click Connect Inspector in the context menu.
The Inspector will automatically connect to the reader.
The Inspector will automatically connect to the reader.
Click the Inspector and then click the Run to this icon (green triangle above the inspector).
In the Translation Parameter Values dialog click Run.
You can watch the loading progress in the Translation Log below the main workspace.
When the run command has completed, the GML table and features will display in the Visual Preview area below the main workspace.
Repeat steps 5 to 7 above for each layer (feature type) you want to view.
You can use FME to convert GML data to other geospatial and non-spatial formats. The instructions below demonstrate how to convert GML data to shapefile, but you can adapt them for different formats.
To convert GML to shapefile in FME Desktop:
Repeat Steps 1 to 4 of the previous section (Loading and displaying the GML supply).
From the Writers tab click Add Writer…
In the Add Writer dialog:
Format: Select ESRI Shapefile.
Dataset: Click …, and navigate to and select the folder in which to save your translated data.
Coord. System: Select ESPG: 27700 (British National Grid).
Click OK.
In the Select Feature Type dialog select the layers you want to convert and click OK.
This dialog may take a while to load. You can watch the progress in the green bar at the bottom left of the FME UI.
Connect each reader to its matching writer by dragging the grey triangle on the reader to the red triangle on the writer.
In the main toolbar click (Run icon) to start the translation.
In the Translation Parameter Values dialog, check that the source and destination file locations are correct and click Run.
You can watch the conversion progress in the Translation Log below the main work area. When the conversion is complete (indicated by a message similar to the one below), both the GML files and Shapefiles will be available in your chosen folders and in the navigator.
These instructions are based on ArcMap version 10.8.1. and assume you have set the default coordinate reference system to British National Grid (EPSG 27700).
if your ArcMap is older than version 10.0, or if you do not have access to the Quick Import (Data Interoperability) extension, use the translation tools available in FME and QGIS to convert the GML data to shapefiles.
You can import GML data into ArcMap using the Quick Import tool that converts the GML into file geodatabase (.gdb).
Due to the large file size, some 5km tiles (especially within larger cities) may take time to process.
Open ArcCatalog and click and (ArcToolbox icon) in top toolbar to open the ArcToolbox.
In ArcToolbox, expand Data Interoperability Tools and click Quick Import.
In the Quick Import dialog, click … (next to the Input Dataset field), and navigate to and select your OS MasterMap Topography GML data.
In the Specify Data Source dialog:
Format: GML SF-0 (Geography Markup Language Simple Features Level SF-0 Profile) will be detected automatically.
Coord. System: Enter British_National_Grid or click … and select it in the dialog.
Click OK.
In the Quick Import dialog:
Output Staging Geodatabase field: Click (file browser icon), navigate to and name the file geodatabase (.gdb) folder, and click Save.
Click OK to start the Quick Import.
When the import process is complete, a message will display in ArcCatalog. To display the GML data in ArcMap:
Open an existing project or create a new one.
In the Add Data dialog:
Select the layers you want to load. You can select multiple layers at the same time to save repeating these steps for each layer in the file geodatabase.
Click Add.
Your geodatabase layers will now display in both the Table of Contents panel and the map area.
As an alternative to using ArcMap’s Quick Import tool (previous section), you can convert your GML data to shapefile using FME and QGIS, and then add the shapefiles directly to ArcMap.
To load shapefiles into ArcMap
Open an existing project or create a new one.
In the Add Data dialog:
Navigate to the shapefiles you want to load. If the relevant folder does not display, click (Connect to Folder icon) and navigate to the file geodatabase folder from there.
Select the shapefiles that you want to load. You can select multiple layers at the same time to save repeating these steps for each shapefile.
Click Add.
Your shapefiles will now appear in both the Table of Contents panel and the map area.
You may need to reorder the layers to see the data correctly. You can reorder layers using drag and drop. We recommend the following layer order: CartographicText, CartographicSymbol, TopographicPoint, BoundaryLine, TopographicLine and TopographicArea.
Ordnance Survey has produced a Standard Styling Specification for OS MasterMap. This is a distinct set of fonts, colours, fill styles and symbols. The specification was developed using a combination of three descriptive attributes: descriptive group, descriptive term and make.
Providing a styling specification has allowed many software providers to develop their own styling (based and adapted from this specification) that can be applied when the data is initially translated so that the data can be displayed immediately with a coherent style.
This section of the specification relates to the product both before and after the descriptive terms upgrade in 2016.
Most geographic information systems (GIS) contain tools that allow customers to choose to make their data display in any preferred manner. Customers can apply their own colours, styles and symbols based on the same three attributes. Alternatively, they can use any of the attributes, either in isolation or in tandem (if their GIS permits), to render the data to their own specification. Attaining a coherent style depends on choosing the attributes carefully. There is little point in using the TOID, for example, as each feature would then need its own colour. You can, however, use the TOID version number to get an idea of how much change has occurred in one area compared to another. In the example below, the darker the red, the higher the version number, and therefore the greater the amount of surveyed change.
This example displays the areas where the greatest amount of change is occurring in the landscape. Having so many attributes allows this to be done without any additional work on the data itself. If a customer’s
own attributes are added to OS MasterMap Topography Layer, these can also be used as the basis for the styling.
Having such flexibility to customise the data presents an opportunity to derive additional value from
OS MasterMap Topography Layer. For example, where there is a necessity to have a clear display of what features look like from a real-world point of view, styling schemes based on this style specification work well. If customers need to view their own data alongside OS MasterMap Topography Layer, they could consider toning down or removing colour from the features so that their data is more contrasted, and therefore has bigger visual impact.
In the example below, a customer has derived a set of grassed areas, coloured and hatched in green, which is displayed over OS MasterMap Topography Layer, with only the buildings highlighted in grey to give some additional definition to the data and to help viewers of the data orientate themselves within the landscape.
The customer’s own data catches the eye first and is the focus of attention. Some systems allow different views of the data, so that one type of styling can be seen by one set of viewers and an entirely different type by another.
OS MasterMap Topography Layer may also be styled just by the line or point features to replicate the engineering style of drawing commonly used in computer-aided design (CAD) systems. The data can even be rendered in black and white to save on printer ink if the printed map is going through various drafts before a final full colour version is produced, or for use in presentations and documents that are only going to be printed in black and white.
In this section, we have discussed how, by adapting the flexibility of OS MasterMap Topography Layer in terms of how it can be displayed, customers can:
Visualise the attributes in thematic maps and derive information from maps in a visual way.
Customise maps to best suit their purpose.
Produce clear, high-quality maps for use in documents, presentations or as hard copies for when it is not possible to access the data through a screen.
The following tables show the attributes used to create the new style rules.
Feature Code | Style Description | Style Code |
---|---|---|
Descriptive Group | Descriptive Term | Make | Style Description | Style Code | Font Code* | Colour Code** |
---|---|---|---|---|---|---|
Geometry | Shape |
---|
Geometry | Shape |
---|
Geometry | Shape |
---|
Geometry | Shape |
---|
Style and Geometry | Shape |
---|
Style and Geometry | Shape |
---|
benchMarkSymbol example style rule, geometry, and visual representation.
Style and Geometry | Shape |
---|
Style and Geometry | Shape |
---|
Style and Geometry | Shape |
---|
This section provides a guide to applying Cartographic style definitions to Topography Layer features.
As landform features and pylons sit on top of topographic areas, they need to be above these in the draw order to be visible.
Styles are not provided for every feature; this means that some features are not drawn when the default styling is applied. This may be for one of several reasons for this, including:
The information is already rendered by another feature.
The information is not easily positioned or styled.
If drawn, the information would be cluttered or confusing.
The information is structural in the data but adds little value for the user by its cartographic depiction.
The information in this section has not been updated to reflect the Descriptive Terms update. Please refer to Addendum A: Cartographic styling for new descriptive terms for the updated terms.
descriptiveGroup | descriptiveTerm | make | Style name |
---|
This section defines the overall logic for applying the style. The order of the property in the condition list below is the order that it is applied; once applied the condition loop is exited.
This example below shows the notation for filtering using the descriptiveGroup and descriptiveTerm attributes; features with multiple descriptiveTerm attributes are discussed in the next section.
This section deals with the techniques for styling features with the descriptiveGroup value of “Natural Environment” that have multiple descriptiveTerm attributes. This section only provides a selection of combinations that were prominent in a study of descriptiveTerm occurrences on natural environment features. The patterns and symbols used are all defined in the pattern definitions section. The logic to apply is as follows:
Property application logic (multiple descriptiveTerm) example:
Table 5: Property application logic (multiple descriptiveTerm).
This section defines the overall logic for applying the style. The order of the property in the condition list below is the order that it is applied; once applied the condition loop is exited.
Total count | feature Code | descriptive Group | descriptive Term | make | physical Presence | Styling description | Code |
---|---|---|---|---|---|---|---|
In the top toolbar, click (Add Data icon).
Navigate to the file geodatabase created in the previous procedure. If the relevant folder does not display, click (Connect to Folder icon) and navigate to the file geodatabase folder from there.
In the top toolbar, click (Add Data icon).
Descriptive Group | Descriptive Term | Make | Style Description | Style Code |
---|---|---|---|---|
Descriptive Group | Descriptive Term | Make | Style Description | Style Code |
---|---|---|---|---|
Descriptive Group | Descriptive Term | Make | Physical Presence | Style Description | Style Code |
---|---|---|---|---|---|
Descriptive Group | Descriptive Term | Style Description | Style Code |
---|---|---|---|
Geometry | Shape |
---|
Geometry | Shape |
---|
Style and Geometry | Shape |
---|
Style and Geometry | Shape |
---|
descriptiveGroup | descriptiveTerm | physicalPresence | make | Style name |
---|
descriptiveGroup | descriptiveTerm | make | Style name |
---|
descriptiveGroup | descriptiveTerm | Style hex value | Font style |
---|
descriptiveGroup | descriptiveTerm | Style (from style guide) |
---|
148 127 807
10046
General Feature
Obstructing
Default Line
1
64 612 785
10019
Building
Outline
Man-made
Obstructing
Building Outline Line
2
29 515 251
10046
General Feature
Edge / Limit
Edge Line
3
10136
Parish Boundary
1
10131
District Boundary
2
10128
Electoral Boundary
3
10127
County Boundary
4
10135
Parliamentary Boundary
5
10091
Culvert Symbol
1
10082
Direction Of Flow Symbol
2
10130
Boundary Half Mereing Symbol
3
10066 or 10170
Bench Mark Symbol
4
10165
Railway Switch Symbol
5
10177
Road Related Flow Symbol
6
Contains ‘Buildings or Structure’
-
-
Building Text
1
1
1
Contains ‘Inland Water’
-
-
Water Text
2
2
2
Contains ‘Road or Track’
-
-
Road Text
3
1
1
Terrain and Height
-
-
Height Text
4
1
3
Contains ‘Roadside’
-
-
Roadside Text
5
1
1
Contains ‘Structure’
-
-
Structure Text
6
2
1
Political or Administrative
-
-
Administrative Text
7
1
5
General Surface
-
Natural
General Surface Natural Text
8
1
1
General Surface
-
Manmade or IS NULL
General Surface Manmade Text
9
1
1
Landform
-
Natural
Landform Natural Text
10
1
4
-
Foreshore
-
Foreshore Text
11
1
4
Contains Tidal Water
-
-
Tidal Water Text
12
2
2
Built Environment
-
-
Built Environment Text
13
1
1
Contains ‘Historic Interest’
-
-
Historic Text
14
3
1
Rail
-
-
Rail Text
15
1
1
Contains ‘General Feature’
-
-
General Feature Text
16
1
1
Landform
-
Manmade
Landform Manmade Text
17
1
4
* Required font 1 = Arial, 2 = Arial Italic, 3 = Times New Roman Italic
** Text colour 1 = Black, 2 = Blue, 3 = Orange, 4 = Brown, 5 = Purple
Contains ‘Buildings’
-
-
Building Text
1
-
-
Water Text
2
Is NULL
Manmade
Building Fill
1
Contains ‘General Surface’
Multi Surface
Multiple
Multi Surface Fill
2
Contains ‘General Surface’
Is NULL
Natural
Natural Fill
3
Contains ‘Road or Track’
Is NULL
Manmade
Road Or Track Fill
4
Contains ‘General Surface’
Is NULL
Manmade or Unknown
Manmade Fill
5
Contains ‘Roadside’
-
Natural
Roadside Natural Fill
6
Contains ‘Roadside’
-
Manmade or Unknown
Roadside Manmade Fill
7
Contains ‘Inland Water’
Is NULL
-
Inland Water Fill
8
Contains ‘Path’
-
-
Path Fill
9
Contains ‘Road or Track’
Track
-
Track Fill
10
-
Slope
-
Slope Fill
11
Contains ‘Structure’
Is NULL OR Upper Level OF Communication OR Overhead Construction
-
Structure Fill
12
-
Cliff
-
Cliff Fill
13
-
Step
-
Step Fill
14
-
Foreshore
-
Foreshore Fill
15
-
Traffic Calming
-
Traffic Calming
16
Glasshouse
-
-
Glasshouse Fill
17
Contains ‘Rail’
Is NULL
Natural
Rail Natural Fill
18
-
Pylon
-
Pylon Fill
19
Contains ‘Building’
Archway
-
Archway Fill
20
Contains ‘Landform’
-
Natural
Landform Natural Fill
21
Contains ‘Tidal Water’
Is NULL
-
Tidal Water Fill
22
Contains ‘Landform’
-
Manmade
Landform Manmade Fill
23
Rail
Is NULL
Manmade or Unknown
Rail Manmade Fill
24
-
-
-
Building Text
1
-
-
Water Text
2
Contains a form of Nonconiferous Trees OR/AND a form of Coniferous Trees
-
Mixed Woodland Fill
25
-
Contains a form of Nonconiferous Trees
-
Nonconiferous Tree Fill
26
-
Contains a form of Coniferous Trees
-
Coniferous Tree Fill
27
-
Contains Orchard
-
Orchard Fill
28
-
Contains Coppice Or Osiers
-
Coppice Or Osiers Fill
29
-
Contains Scrub
-
Scrub Fill
30
-
Contains Boulders
-
Boulders Fill
31
-
Contains Rock
-
Rock Fill
32
-
Contains Scree
-
Scree Fill
33
-
Contains Rough Grassland
-
Rough Grassland Fill
34
-
Contains Heath
-
Heath Fill
35
-
Contains Marsh
-
Marsh Fill
36
Unclassified
99
Contains ‘General Feature’
Is NULL
-
Obstructing
Default Line
1
Contains ‘Building’
Outline
Manmade
Obstructing
Building Outline Line
2
Contains ‘General Feature’
Is NULL
-
Edge / Limit
Edge Line
3
Contains ‘Road Or Track’
Public
Manmade
Edge / Limit
Road Or Track Line
4
Contains ‘Building’
Division
Manmade
Obstructing
Building Division Line
5
-
Polygon Closing Link
-
-
Polygon Closing Line
6
Contains ‘Inland Water’
Is NULL
-
Edge / Limit
Inland Water Line
7
-
Inferred Property Closing Link
-
-
Property Closing Line
8
Contains ‘General Surface’
Is NULL
Natural
Edge / Limit
General Surface Natural Line
9
Contains ‘Building’
Outline
Manmade
Overhead
Building Overhead Line
10
-
Bottom Of Slope
Bottom Of Slope Line
11
-
Top Of Slope
-
-
Top Of Slope Line
12
-
Step
-
-
Step Line
13
-
Unmade Path Alignment
-
-
Path Line
14
-
Mean High Water (Springs)
-
-
Mean High Water Line
15
-
Traffic Calming
-
-
Traffic Calming Line
16
-
Standard Gauge Track
-
-
Standard Gauge Track Line
17
-
Bottom Of Cliff
-
-
Bottom Of Cliff Line
18
-
Top Of Cliff
-
-
Top Of Cliff Line
19
-
Mean Low Water (Springs)
-
-
Mean Low Water Line
20
-
Overhead Construction
-
-
Overhead Construction Line
21
-
Culvert
-
-
Culvert Line
22
-
Pylon
-
-
Pylon Line
23
Landform
-
Natural
-
Landform Natural Line
24
Unclassified
-
-
-
Unclassified Line
99
-
Ridge Or Rock Line
-
-
Ridge Or Rock Line
25
Historic Interest
-
-
-
Historic interest Line
26
-
Narrow Gauge
-
-
Narrow Gauge Line
27
-
Buffer
-
-
Railway Buffer Line
28
-
Tunnel Edge
-
-
Tunnel Edge Line
29
Landform
-
Manmade
-
Landform Manmade Line
30
-
-
-
-
Unclassified
99
-
Spot Height
Spot Height Point
1
-
Emergency Telephone
Emergency Telephone Point
2
-
Site of Heritage
Site Of Heritage Point
3
-
Culvert
Culvert Point
4
-
Positioned Nonconiferous Tree
Positioned Nonconiferous Tree Point
5
Inland Water
-
Inland Water Point
6
Roadside
-
Roadside Point
7
-
Overhead Construction
Overhead Construction Point
8
Rail
-
Rail Point
9
-
Positioned Coniferous Tree
Positioned Coniferous Tree
10
-
Boundary Post Or Stone
Boundary Post Point or Stone Point
11
-
Triangulation Point Or Pillar
Triangulation Point Or Pillar Point
12
Historic Interest
-
Historical Interest Point
13
Landform
Positioned Boulder
Landform Point
14
Tidal Water
-
Tidal Water Point
15
Structure
-
Structure Point
16
10080
-
Positioned Nonconiferous Tree Point
3
10120
-
Inland Water Point
4
10176
-
Inland Water Point
4
10159
-
Inland Water Point
4
Unclassified
99
Structure | Capstan | Manmade | pointSymbol |
Historic Interest + Structure | Cave | caveSymbol |
Landform | Cave | Natural | caveSymbol |
Structure | Chimney | Manmade | pointSymbol |
Inland Water | Collects | Natural | waterPointSymbol |
Structure | Crane | Manmade | pointSymbol |
Structure | Crane + Overhead Construction | Manmade | pointSymbol |
Political Or Administrative + Structure | Boundary Post Or Stone + Cross | Manmade | boundaryPostSymbol |
Historic Interest + Structure | Cross | Manmade | crossSymbol |
Historic Interest + Structure | Cross + Site Of Heritage | Manmade | heritageSiteOfSymbol |
Structure | Cross | Manmade | crossSymbol |
Historic Interest + Inland Water + Structure | Cross + Well | Manmade | waterPointSymbol |
Historic Interest + Inland Water + Structure | Cross + Site Of Heritage + Well | Manmade | heritageSiteOfSymbol |
Political Or Administrative + Roadside + Structure | Boundary Post Or Stone + Distance Marker | Manmade | boundaryPostSymbol |
Political Or Administrative + Structure | Boundary Post Or Stone + Distance Marker | Manmade | boundaryPostSymbol |
Rail + Structure | Distance Marker | Manmade | pointSymbol |
Historic Interest + Structure | Distance Marker | Manmade | pointSymbol |
Structure | Distance Marker | Manmade | pointSymbol |
Roadside + Structure | Distance Marker | Manmade | pointSymbol |
Historic Interest + Structure | Distance Marker + Site Of Heritage | Manmade | heritageSiteOfSymbol |
Structure | Electricity Sub Station | Manmade | pointSymbol |
Structure | Emergency Telephone | Manmade | emergencyTelephoneSymbol |
Political Or Administrative + Structure | Boundary Post Or Stone + Flagstaff | Manmade | boundaryPostSymbol |
Structure | Flagstaff | Manmade | pointSymbol |
Inland Water | Ford | Natural | waterPointSymbol |
Tidal Water | Ford | Natural | waterPointSymbol |
Inland Water + Structure | Fountain | Manmade | pointSymbol |
Structure | Gas Governor | Manmade | pointSymbol |
Historic Interest + Political Or Administrative + Structure | Boundary Post Or Stone + Guide Post | Manmade | boundaryPostSymbol |
Political Or Administrative + Roadside + Structure | Boundary Post Or Stone + Guide Post | Manmade | boundaryPostSymbol |
Roadside + Structure | Guide Post | Manmade | pointSymbol |
Historic Interest + Roadside + Structure | Guide Post | Manmade | pointSymbol |
Historic Interest + Roadside + Structure | Guide Post + Site Of Heritage | Manmade | heritageSiteOfSymbol |
Inland Water | Culvert + Issues | Manmade | waterPointSymbol |
Inland Water | Issues | Manmade | waterPointSymbol |
Structure | Letter Box | Manmade | postboxSymbol |
Structure | Mast | Manmade | pointSymbol |
Historic Interest + Structure | Mast | Manmade | pointSymbol |
Historic Interest + Structure | Mast + Site Of Heritage | Manmade | heritageSiteOfSymbol |
Roadside + Structure | Mast | Manmade | pointSymbol |
Structure | Mooring Post | Manmade | pointSymbol |
Structure | Pole | Manmade | pointSymbol |
Structure | Overhead Construction + Pole | Manmade | pointSymbol |
Rail + Structure | Pole | Manmade | pointSymbol |
Political Or Administrative + Structure | Boundary Post Or Stone + Post | Manmade | boundaryPostSymbol |
Historic Interest + Political Or Administrative + Structure | Boundary Post Or Stone + Post | Manmade | boundaryPostSymbol |
Structure | Post | Manmade | pointSymbol |
Historic Interest + Structure | Post | Manmade | pointSymbol |
Rail + Structure | Post | Manmade | pointSymbol |
Roadside + Structure | Post | Manmade | pointSymbol |
Historic Interest + Structure | Post + Site Of Heritage | Manmade | heritageSiteOfSymbol |
Structure | Public Convenience | Manmade | pointSymbol |
Structure | Public Telephone | Manmade | pointSymbol |
Rail + Structure | Signal | Manmade | signalSymbol |
Structure | Signal | Manmade | signalSymbol |
Inland Water | Sinks | Natural | waterPointSymbol |
Structure | Sluice | Manmade | waterPointSymbol |
Inland Water | Spreads | Natural | waterPointSymbol |
Inland Water | Culvert + Spring | Manmade | waterPointSymbol |
Inland Water | Spring | Manmade | waterPointSymbol |
Historic Interest + Inland Water | Spring | Natural | waterPointSymbol |
Inland Water | Spring | Natural | waterPointSymbol |
Historic Interest + Inland Water | Spring + Site of Heritage | Natural | heritageSiteOfSymbol |
Inland Water | Static Water | waterPointSymbol |
Structure | Pylon + Tank | Manmade | pointSymbol |
Structure | Telecommunications Mast | Manmade | pointSymbol |
Inland Water | Waterfall (vertical) | Natural | waterPointSymbol |
Structure | Weir | Manmade | pointSymbol |
Historic Interest + Inland Water + Structure | Site Of Heritage + Well | Manmade | heritageSiteOfSymbol |
Historic Interest + Inland Water | Well | Manmade | waterPointSymbol |
Inland Water + Structure | Well | Manmade | pointSymbol |
Inland Water | Well | Manmade | waterPointSymbol |
Historic Interest + Structure | Well | Manmade | pointSymbol |
Structure | Well | Manmade | pointSymbol |
Structure | Wind Turbine | Manmade | pointSymbol |
Structure | Pylon + Wind Turbine | Manmade | pointSymbol |
General Surface | Agricultural Land | Natural | agriculturalLandFill |
General Surface + Structure | Aqueduct | Manmade | structureFill |
Inland Water + Structure | Aqueduct + Watercourse | Manmade | constructedWaterFill |
Structure | Bridge | Manmade | structureFill |
Structure | Capstan | Manmade | structureFill |
Landform | Cave | Natural | naturalLandformPattern |
Inland Water | Canal | Natural | constructedWaterFill |
Tidal Water | Canal | Natural | constructedWaterFill |
Inland Water | Canal Feeder | Natural | inlandWaterFill |
Building | Chimney | Manmade | buildingFill |
Structure | Chimney | Manmade | structureFill |
Inland Water | Collects | Natural | naturalEnvironmentFill with collectsAndSpreadsFillSymbol and collectsAndSpreadsPattern |
Inland Water | Conduit | Manmade | constructedWaterFill |
Inland Water + Structure | Conduit | Manmade | constructedWaterFill |
Building | Conduit | Manmade | buildingFill |
Structure | Conveyor | Manmade | structureFill |
Building + Structure | Conveyor | Manmade | buildingFill |
Structure | Crane | Manmade | structureFill |
Building + Structure | Crane | Manmade | buildingFill |
Structure | Cross | Manmade | structureFill |
Inland Water | Drain | Natural | constructedWaterFill |
Tidal Water | Drain | Natural | constructedWaterFill |
Building | Electricity Sub Station | Manmade | buildingFill |
General Surface | Electricity Sub Station | Manmade | madeSurfaceFill |
Structure | Electricity Sub Station | Manmade | structureFill |
Path + Structure | Footbridge | Manmade | structureFill |
Building + Structure | Footbridge | Manmade | buildingFill |
Inland Water + Road Or Track | Ford | Natural | constructedWaterFill |
Road Or Track + Tidal Water | Ford | Natural | constructedWaterFill |
Inland Water + Structure | Fountain | Manmade | constructedWaterFill |
Building | Gantry | Manmade | buildingFill |
Structure | Gantry | Manmade | structureFill |
Building | Gas Governor | Manmade | buildingFill |
General Surface | Gas Governor | Manmade | madeSurfaceFill |
Structure | Gas Governor | Manmade | structureFill |
Structure | Groyne | Manmade | structureFill |
General Surface | Landfill | Manmade | multipleSurfaceFill |
Landform | Landfill | Manmade | multipleSurfaceFill |
General Surface | Landfill (Inactive) | Natural | multipleSurfaceFill |
Landform | Landfill (Inactive) | Natural | multipleSurfaceFill |
Rail + Road Or Track | Level Crossing | Manmade | roadFill |
Structure | Lighting Gantry | Manmade | structureFill |
Rail + Structure | Lighting Gantry | Manmade | structureFill |
Inland Water | Lock | Manmade | constructedWaterFill |
Inland Water + Structure | Lock | Manmade | constructedWaterFill |
Structure | Lock Gate | Manmade | structureFill |
Natural Environment | Marsh | Natural | naturalEnvironmentFill with marshFillSymbol and marshPattern |
Natural Environment + Rail | Marsh | Natural | naturalEnvironmentFill with marshFillSymbol and marshPattern |
Natural Environment + Structure | Marsh | Natural | naturalEnvironmentFill with marshFillSymbol and marshPattern |
Natural Environment + Roadside | Marsh | Natural | naturalEnvironmentFill with marshFillSymbol and marshPattern |
Historic Interest + Structure | Mast | Manmade | structureFill |
Structure | Mast | Manmade | structureFill |
Inland Water | Mill Leat | Manmade | constructedWaterFill |
Inland Water | Mine Leat | Manmade | constructedWaterFill |
Inland Water + Structure | Mine Leat | Manmade | constructedWaterFill |
General Surface | Mineral Workings | Manmade | multipleSurfaceFill |
Landform | Mineral Workings | Manmade | multipleSurfaceFill |
General Surface | Mineral Workings (Inactive) | Natural | multipleSurfaceFill |
Landform | Mineral Workings (Inactive) | Natural | multipleSurfaceFill |
General Surface | Mud | Natural | mudFill |
General Surface | Mud + Sand | Natural | mudFill with sandFillSymbol and sandPattern |
General Surface | Mud + Shingle | Natural | mudFill with shingleFillSymbol and shinglePattern |
Natural Environment + Tidal Water | Foreshore + Mud | Natural | mudFill |
Natural Environment + Tidal Water | Foreshore + Mud + Sand | Natural | mudFill with sandFillSymbol and sandPattern |
Natural Environment + Tidal Water | Foreshore + Mud + Shingle | Natural | mudFill with shingleFillSymbol and shinglePattern |
Building | Public Convenience | Manmade | buildingFill |
General Surface | Public Convenience | Manmade | multipleSurfaceFill |
Structure | Public Convenience | Manmade | structureFill |
Building | Rail Signal Gantry | Manmade | buildingFill |
Rail + Structure | Rail Signal Gantry | Manmade | structureFill |
Natural Environment + Tidal Water | Reeds | Natural | tidalWaterFill with reedsFillSymbol and reedsPattern |
Inland Water + Natural Environment | Reeds + Static Water | Natural | inlandWaterFill with reedsFillSymbol and reedsPattern |
Natural Environment + Tidal Water | Foreshore + Reeds | Natural | tidalWaterFill with reedsFillSymbol and reedsPattern |
Inland Water + Natural Environment | Reeds + Reservoir | Natural | constructedWaterFill with reedsFillSymbol and reedsPattern |
Inland Water | Reservior | Natural | constructedWaterFill |
Natural Environment | Saltmarsh | Natural | naturalEnvironmentFill with saltmarshFillSymbol and saltmarshPattern |
Natural Environment + Rail | Saltmarsh | Natural | naturalEnvironmentFill with saltmarshFillSymbol and saltmarshPattern |
Natural Environment + Roadside | Saltmarsh | Natural | naturalEnvironmentFill with saltmarshFillSymbol and saltmarshPattern |
Natural Environment + Tidal Water | Saltmarsh | Natural | tidalWaterFill with saltmarshFillSymbol and saltmarshPattern |
General Surface | Sand | Natural | sandFill with sandFillSymbol and sandPattern |
Roadside | Sand | Natural | sandFill with sandFillSymbol and sandPattern |
Rail | Sand | Natural | sandFill with sandFillSymbol and sandPattern |
Natural Environment + Tidal Water | Foreshore + Sand | Natural | sandFill with sandFillSymbol and sandPattern |
General Surface | Shingle | Natural | shingleFill with shingleFillSymbol and shinglePattern |
Natural | Foreshore + Shingle | Natural | shingleFill with shingleFillSymbol and shinglePattern |
Roadside | Shingle | Natural | shingleFill with shingleFillSymbol and shinglePattern |
Rail | Shingle | Natural | shingleFill with shingleFillSymbol and shinglePattern |
Inland Water | Sinks | Natural | inlandWaterFill |
General Surface | Slipway | Manmade | madeSurfaceFill |
General Surface + Tidal Water | Foreshore + Slipway | Manmade | madeSurfaceFill |
General Surface + Structure | Slipway | Manmade | madeSurfaceFill |
General Surface | Slag Heap | Manmade | multipleSurfaceFill |
General Surface | Slag Heap (Inactive) | Natural | multipleSurfaceFill |
General Surface + Tidal Water | Foreshore + Sloping Masonry | Manmade | slopingMasonryFill |
General Surface | Sloping Masonry | Manmade | slopingMasonryFill |
Path + Structure | Sloping Masonry | Manmade | slopingMasonryFill |
Rail | Sloping Masonry | Manmade | slopingMasonryFill |
Roadside | Sloping Masonry | Manmade | slopingMasonryFill |
General Surface | Spoil Heap | Manmade | multipleSurfaceFill |
General Surface | Spoil Heap (Inactive) | Natural | multipleSurfaceFill |
General Surface + Tidal Water | Foreshore + Spreads | Natural | tidalWaterFill with collectsAndSpreadsFillSymbol and collectsAndSpreadsPattern |
General Surface | Spreads | Natural | naturalEnvironmentFill with collectsAndSpreadsFillSymbol and collectsAndSpreadsPattern |
Historic Interest + Inland Water | Spring | Natural | inlandWaterFill |
Inland Water | Spring | Natural | inlandWaterFill |
Inland Water + Structure | Spring | Natural | inlandWaterFill |
Inland Water | Static Water | Natural | inlandWaterFill |
Inland Water | Static Water | Manmade | inlandWaterFill |
General Surface + Tidal Water | Swimming Pool | Manmade | constructedWaterFill |
Inland Water | Swimming Pool | Manmade | constructedWaterFill |
Building | Tank | Manmade | buildingFill |
Building + Structure | Tank | Manmade | buildingFill |
General Surface | Tank | Manmade | structureFill |
General Surface | Tank | Natural | structureFill |
Structure | Tank | Manmade | structureFill |
Inland Water + Structure | Tank | Natural | inlandWaterFill |
Inland Water + Structure | Tank | Manmade | inlandWaterFill |
Structure | Telecommunications Mast | Manmade | structureFill |
Inland Water | Watercourse | Natural | inlandWaterFill |
Inland Water | Waterfall | Natural | inlandWaterFill |
Structure + Tidal Water | Foreshore + Weir | Manmade | tidalWaterFill |
Inland Water + Structure | Weir | Manmade | inlandWaterFill |
Building | well | Manmade | buildingFill |
Inland Water + Structure | Well | Manmade | buildingFill |
Building | Well | Manmade | buildingFill |
Building + Historic Interest | Well | Manmade | buildingFill |
Building | Wind Turbine | Manmade | buildingFill |
Structure | Wind Turbine | Manmade | structureFill |
Building | Manmade | buildingFill |
Building | Archway | Manmade | buildingFill |
General Surface | Manmade | madeSurfaceFill |
General Surface | Multiple | multipleSurfaceFill |
General Surface | Natural | naturalSurfaceFill |
General Surface | Unknown | madeSurfaceFill |
General Surface | Multi Surface | Multiple | multipleSurfaceFill |
General Surface | Step | Manmade | stepFill |
Glasshouse | Manmade | glasshouseFill |
Inland Water | Natural | inlandWaterFill |
Landform | Manmade | manmadeLandformPattern |
Landform | Natural | naturalLandformPattern |
Landform | Cliff | Natural | naturalLandformPattern |
Landform | Slope | Manmade | manmadeLandformPattern |
Natural Environment | Boulders | Natural | naturalEnvironmentFill and bouldersPattern |
Natural Environment | Boulders (Scattered) | Natural | naturalEnvironmentFill and scatteredBouldersPattern |
Natural Environment | Coniferous Trees | Natural | naturalEnvironmentFill and coniferousTreesPattern |
Natural Environment | Coniferous Trees (Scattered) | Natural | naturalEnvironmentFill and scatteredConiferousTreesPattern |
Natural Environment | Coppice Or Osiers | Natural | naturalEnvironmentFill and coppicePattern |
Natural Environment | Heath | Natural | naturalEnvironmentFill and heathPattern |
Natural Environment | Marsh Reeds Or Saltmarsh | Natural | naturalEnvironmentFill and marshPattern |
Natural Environment | Nonconiferous Trees | Natural | naturalEnvironmentFill and nonconiferousTreesPattern |
Natural Environment | Nonconiferous Trees (Scattered) | Natural | naturalEnvironmentFill and scatteredNonconiferousTreesPattern |
Natural Environment | Orchard | Natural | naturalEnvironmentFill and orchardPattern |
Natural Environment | Rock | Natural | naturalEnvironmentFill and rocksPattern |
Natural Environment | Rock (Scattered) | Natural | naturalEnvironmentFill and scatteredRocksPattern |
Natural Environment | Rough Grassland | Natural | naturalEnvironmentFill and roughGrassPattern |
Natural Environment | Scree | Natural | naturalEnvironmentFill and screePattern |
Natural Environment | Scrub | Natural | naturalEnvironmentFill and scrubPattern |
Path | Manmade | pathFill |
Path | Step | Manmade | stepFill |
Rail | Manmade | railFill |
Rail | Unknown | madeSurfaceFill |
Rail | Natural | naturalSurfaceFill |
Road Or Track | Manmade | roadFill |
Road Or Track | Traffic Calming | Manmade | roadFill |
Roadside | Manmade | madeSurfaceFill |
Roadside | Unknown | madeSurfaceFill |
Roadside | Natural | naturalSurfaceFill |
Structure | structureFill |
Structure | Manmade | structureFill |
Structure | Overhead Construction | Manmade | structureFill |
Structure | Pylon | Manmade | structureFill |
Structure | Upper Level Of Communication | Manmade | structureFill |
Tidal Water | Natural | tidalWaterFill |
Tidal Water | Foreshore | Natural | tidalWaterFill and foreshorePattern |
if | descriptiveGroup = ‘Building’ | then apply | buildingFill |
or | descriptiveTerm = ‘Step’ | then apply | stepFill |
or | descriptiveGroup = ‘Glasshouse’ | then apply | glasshouseFill |
or | descriptiveGroup = ‘Historic Interest’ | then apply | heritageFill |
or | descriptiveGroup = ‘Inland Water’ | then apply | inlandWaterFill |
or | descriptiveGroup = ‘Natural Environment’ | then apply | naturalEnvironmentFill |
or | descriptiveGroup = ‘Path’ | then apply | pathFill |
or | descriptiveGroup = ‘Road Or Track’ | then apply | roadFill |
or | descriptiveGroup = ‘Structure’ | then apply | structureFill |
or | descriptiveGroup = ‘Tidal Water’ | then apply | tidalWaterFill |
or | descriptiveGroup = ‘Unclassified’ | then apply | unclassifiedFill |
or | descriptiveGroup = ‘Rail’ and make = ‘Manmade’ | then apply | railFill |
or | make = ‘Manmade’ | then apply | madeSurfaceFill |
or | make = ‘Natural’ | then apply | naturalSurfaceFill |
or | make = ‘Unknown’ | then apply | madeSurfaceFill |
or | make = ‘Multiple’ | then apply | multipleSurfaceFill |
else | apply | unclassifiedFill |
if | descriptiveGroup = ‘Natural Environment’ | then |
If | Number of descriptiveTerm attributes = 3 | then apply | relevant pattern for type combinations (see Pattern definitions) |
or | Number of descriptiveTerm attributes = 2 | then apply | relevant pattern for type combinations (see Pattern definitions) |
or | Number of descriptiveTerm attributes = 1 | then apply | relevant pattern for type |
else |
| apply | multiVegetationPattern (seePattern definitions) |
Building | Outline | Obstructing | Manmade | buildingLine |
Building | Outline | Overhead | Manmade | buildingOverheadLine |
Building | Division | Obstructing | Manmade | buildingLine |
General Feature | Obstructing | defaultLine |
General Feature | Overhead Construction | structureOverheadLine |
General Feature | Edge/Limit | defaultDashedLine |
General Feature | Minor Detail | defaultLine |
General Feature | Tunnel Edge | Edge/Limit | defaultUndergroundLine |
General Surface | Edge/Limit | Natural | defaultDashedLine |
General Surface | Step | Edge/Limit | Manmade | defaultLine |
General Surface | Step | Manmade | defaultLine |
Historic Interest | Course Of Heritage | defaultUndergroundLine |
Historic Interest | Minor Detail | defaultLine |
Inland Water | Tunnel Edge | Edge/Limit | defaultUndergroundLine |
Inland Water | Minor Detail | Manmade | waterLine |
Inland Water | Culvert | Manmade | waterLine |
Inland Water | Edge/Limit | waterLine |
Landform | Top Of Slope | Edge/Limit | Manmade | landformBoldLine |
Landform | Edge/Limit | Natural | landformLine |
Landform | Edge/Limit | Manmade | landformLine |
Landform | Bottom Of Cliff | Edge/Limit | Natural | landformLine |
Landform | Ridge Or Rock Line | Natural | landformLine |
Landform | Top Of Cliff | Edge/Limit | Natural | landformBoldLine |
Landform | Bottom Of Slope | Edge/Limit | Manmade | landformLine |
Network Or Polygon Closing Geometry | Inferred Property Closing Link | Closing | closingLine |
Network Or Polygon Closing Geometry | Polygon Closing Link | Closing | closingLine |
Path | Tunnel Edge | Edge/Limit | Manmade | defaultUndergroundLine |
Political Or Administrative | District | Boundary | districtLine |
Political Or Administrative | Electoral | Boundary | electoralLine |
Political Or Administrative | Parliamentary | Boundary | parliamentaryLine |
Political Or Administrative | County | Boundary | countyLine |
Political Or Administrative | Parish | Boundary | parishLine |
Rail | Narrow Gauge | Network | narrowGaugeRailwayAlignmentLine |
Rail | Standard Gauge Track | standardGaugeRailLine |
Rail | Buffer | Manmade | defaultLine |
Rail | Minor Detail | defaultLine |
Rail | Tunnel Edge | Edge/Limit | defaultUndergroundLine |
Road Or Track | Tunnel Edge | Edge/Limit | Manmade | defaultUndergroundLine |
Road Or Track | Public | Edge/Limit | Manmade | defaultDashedLine |
Road Or Track | Traffic Calming | Edge/Limit | Manmade | defaultDashedLine |
Roadside | Minor Detail | defaultLine |
Structure | Minor Detail | Manmade | defaultLine |
Structure | Pylon | Edge/Limit | Manmade | defaultLine |
Tidal Water | Mean High Water (Springs) | Edge/Limit | Natural | waterBoldLine |
Tidal Water | Mean Low Water (Springs) | Edge/Limit | Natural | waterDashedLine |
If | descriptiveGroup = ‘Building’ and physicalPresence = ‘Overhead’ | then apply | buildingOverheadLine |
or | descriptiveTerm = ‘Overhead Construction’ | then apply | structureOverheadLine |
or | descriptiveTerm = ‘Tunnel Edge’ | then apply | defaultUndergroundLine |
or | descriptiveGroup = ‘Building’ | then apply | buildingLine |
or | descriptiveTerm = ‘Mean High Water (Springs)’ | then apply | waterBoldLine |
or | descriptiveTerm = ‘Mean Low Water (Springs)’ | then apply | waterDashedLine |
or | descriptiveGroup = ‘Inland Water’ | then apply | waterLine |
or | descriptiveTerm = ‘Narrow Gauge’ | then apply | narrowGaugeRailwayAlignmentLine |
or | descriptiveTerm = ‘Standard Gauge Track’ | then apply | standardGaugeRailLine |
or | descriptiveGroup = ‘Landform’ and descriptiveTerm = ‘Top Of Slope’ | then apply | landformBoldLine |
or | descriptiveGroup = ‘Landform’ and descriptiveTerm = ‘Top Of Cliff’ | then apply | landformBoldLine |
or | descriptiveGroup = ‘Landform’ and descriptiveTerm = ‘Bottom Of Slope’ | then apply | landformLine |
or | descriptiveGroup = ‘Landform’ and descriptiveTerm = ‘Bottom Of Cliff’ | then apply | landformLine |
or | descriptiveTerm = ‘Parish’ | then apply | parishLine |
or | descriptiveTerm = ‘Electoral’ | then apply | electoralLine |
or | descriptiveTerm = ‘County’ | then apply | countyLine |
or | descriptiveTerm = ‘Parliamentary’ | then apply | parliamentaryLine |
or | descriptiveTerm = ‘District’ | then apply | districtLine |
or | physicalPresence = ‘Edge/Limit’ | then apply | defaultDashedLine |
or | physicalPresence = ‘Closing’ | then apply | closingLine |
Else | apply | defaultLine |
General Feature | Positioned Nonconiferous Tree | Natural | positionedNonconiferousTreeSymbol |
General Feature | Positioned Coniferous Tree | Natural | positionedConiferousTreeSymbol |
General Feature | Positioned Boulder | Natural | positionedBoulderSymbol |
Historic Interest | Site Of Heritage | heritageSiteOfSymbol |
Historic Interest | Structure | pointSymbol |
Inland Water | Manmade | waterPointSymbol |
Landform | Manmade | pointSymbol |
Landform | Disused Feature | Natural | landformDisusedSymbol |
Landform | Natural | pointSymbol |
Political Or Administrative | Boundary Post Or Stone | boundaryPostSymbol |
Rail | Structure | pointSymbol |
Roadside | pointSymbol |
Structure | Manmade | pointSymbol |
Structure | Structure | Manmade | pointSymbol |
Structure | Triangulation Point Or Pillar | Manmade | triangulationStationSymbol |
Terrain And Height | Spot Height | spotHeightSymbol |
Tidal Water | waterPointSymbol |
Buildings Or Structure | 000000 | Normal |
Built Environment | Compound | 000000 | Normal |
General Feature | 000000 | Normal |
General Surface | 000000 | Normal |
Height Control | Bench Mark | 000000 | Normal |
Historic Interest | 000000 | Italic |
Inland Water | 0099FF | Normal |
Landform | 000000 | Normal |
Political Or Administrative | FF00FF | Normal |
Rail | 000000 | Normal |
Road Or Track | Road Name Or Classification | 000000 | Normal |
Roadside | 000000 | Normal |
Structure | 000000 | Normal |
Terrain And Height | 000000 | Normal |
Tidal Water | Foreshore | 0099FF | Normal |
Tidal Water | 0099FF | Normal |
Height Control | Bench Mark | benchMarkSymbol |
Inland Water | Culvert | culvertSymbol |
Inland Water | Direction Of Flow | flowArrowSymbol |
Political Or Administrative | Boundary Half Mereing | boundaryMereingChangeSymbol |
Road Or Track | Road Related Flow | roadFlowSymbol |
Rail | Switch | railwaySwitchSymbol |
General Feature | Cattle Grid | Edge/Limit | defaultDashedLine |
General Feature | Cattle Grid | Obstructing | defaultLine |
Inland Water | Canal Feeder | Edge/Limit | waterLine |
Inland Water | Collects | Edge/Limit | waterLine |
Inland Water | Conduit | Edge/Limit | waterLine |
Inland Water + Structure | Conduit | Edge/Limit | waterLine |
Inland Water + Structure | Conduit | Obstructing | defaultLine |
General Feature | Conveyor | Obstructing | defaultLine |
General Feature | Conveyor | defaultLine |
General Feature | Crane + Overhead Construction | defaultDashedLine |
Inland Water | Drain | waterLine |
Inland Water | Ford | Edge/Limit | waterLine |
General Feature | Gantry + Overhead Construction | defaultDashedLine |
General Feature | Groyne | Obstructing | seaDefenceLine |
Inland Water | Culvert + Issues | Edge/Limit | waterLine |
General Feature | Lighting Gantry + Overhead Construction | defaultDashedLine |
General Feature | Line Of Mooring Posts | postsLine |
General Feature | Line Of Posts | postsLine |
General Feature | Lock Gate | Obstructing | defaultLine |
Inland Water | Mill Leat | Edge/Limit | waterLine |
Inland Water | Mine Leat | Edge/Limit | waterLine |
Inland Water + Structure | Mine Leat | Edge/Limit | waterLine |
Building + Tidal Water | Mean High Water (Springs) + Normal Tidal Limit + Outline | Obstructing | Manmade | waterBoldLine |
General Feature + Tidal Water | Mean High Water (Springs) + Normal Tidal Limit | Edge/Limit | waterBoldLine |
General Feature + Tidal Water | Mean High Water (Springs) + Normal Tidal Limit | Obstructing | waterBoldLine |
Structure + Tidal Water | Mean High Water (Springs) + Normal Tidal Limit | Obstructing | Manmade | waterBoldLine |
Tidal Water | Mean High Water (Springs) + Normal Tidal Limit | Edge/Limit | Natural | waterBoldLine |
General Feature | Overhead Construction + Rail Signal Gantry | defaultDashedLine |
General Feature | Slipway | Edge/Limit | defaultLine |
General Feature | Sloping Masonry | Edge/Limit | defaultLine |
General Feature | Sluice | Obstructing | Manmade | defaultLine |
Inland Water | Spreads | Edge/Limit | waterLine |
General Feature | Spring | Obstructing |
Inland Water | Culvert + Spring | Edge/Limit |
Inland Water | Watercourse | Edge/Limit |
Inland Water | Waterfall | Edge/Limit | Natural |
General Feature | Waterfall (vertical) | Edge/Limit | Natural |
Inland Water + Structure | Weir | Obstructing |
Structure + Tidal Water | Mean High Water (Springs) + Weir | Obstructing | Manmade |
If GeoPackage format is selected, the filename will be constructed as: OSMasterMapTopography_gpkg_<order number>.zip
Where:
order number is your customer order number.
Within the zip file, there will be a Data folder (containing six GeoPackage files – one file per feature type)
and a Doc folder (containing licence and readme files):
Data folder
OSMasterMapTopography_<order number>_boundary_line.gpkg
OSMasterMapTopography_<order number>_cartographic_symbol.gpkg
OSMasterMapTopography_<order number>_cartographic_text.gpkg
OSMasterMapTopography_<order number>_topographic_area.gpkg
OSMasterMapTopography_<order number>_topographic_line.gpkg
OSMasterMapTopography_<order number>_topographic_point.gpkg
Doc folder: <licence and readme files>
If vector tiles format is selected, the file name will be constructed as: OSMasterMapTopography_mbtiles_gb.zip
Within the zip file, there will be a Data folder (containing six MBTiles files – one file per feature type) and a Doc folder (containing licence and readme files):
Data folder
OSMasterMapTopography_gb_BoundaryLine.mbtiles
OSMasterMapTopography_gb_CartographicSymbol.mbtiles
OSMasterMapTopography_gb_CartographicText.mbtiles
OSMasterMapTopography_gb_TopographicArea.mbtiles
OSMasterMapTopography_gb_TopographicLine.mbtiles
OSMasterMapTopography_gb_TopographicPoint.mbtiles
Doc folder: <licence and readme files>
If geographic chunk data supply is used, the file name will be constructed as: orderNumber-ngxxyy.gz Where:
orderNumber is your customer order number.
ngxxyy is the chunk name plus the four-digit grid reference belonging to the 1km south-west corner of the 2km / 5km / 10km chunk being supplied.
For example: 1234567-SU4020.gz
If non-geographic chunk data supply is selected, the file name will be constructed as: orderNumber- vvvvvv.gz
Where:
orderNumber is your customer order number.
vvvvvv is the volume number of the file.
For example: 1234567-000001.gz
OS MasterMap Topography Layer orders are fulfilled via the OS Data Hub’s download service. However, in exceptional circumstances, OS will supply the product via CD, DVD, an SFTP server or a download service, on a minimum six-week cycle.
Full Great Britain coverage is available by ordering a National Set (GB) in GML or vector tiles formats only. Smaller areas can be ordered by selecting an AOI through the online ordering system in GML or GeoPackage formats only.
More information about supply options can be found in the product's Overview, which is available from the OS MasterMap Topography Layer Product Support page of the OS website.
In GML format, OS MasterMap Topography Layer is split into chunks to allow file sizes to be kept at a manageable level. Two types of chunks are available: geographic and non-geographic. A more detailed description of these options can be found in the product's Overview, which is available from the
OS MasterMap Topography Layer Product Support page of the OS website.
Geographic chunking divides supply areas into manageable sizes in a geographically meaningful way. Chunks are created to a user-specified size, either 2km by 2km, 5km by 5km, or 10km by 10km. Features that fall within two or more chunks are supplied in both chunks, meaning that some features around the chunk edges will be duplicated.
Non-geographic chunking divides supply areas into files that have a fixed nominal size, regardless of geographic area. There are three compressed file size options available: 10MB, 30MB or 50MB. Each feature will only appear in one chunk file. It is possible for features from various geographic locations to appear in one file, and for adjacent features to be supplied in different files.
Administrative boundaries are defined as showing the limits of responsibility and representation for electoral and administrative purposes. Boundary alignments are shown within the Administrative Boundaries theme. As well as the boundary’s relationship to real-world objects, its mereing and boundary descriptions, where needed for clarification, are also supplied.
The following types of boundary are shown within the Administrative Boundaries theme:
County Constituency
Borough Constituency (England and Wales)
Burgh Constituency (Scotland)
Assembly Electoral Region and Assembly Constituency (Wales)
Parliamentary Electoral Region and Parliamentary Constituency (Scotland)
County
City and County of London, District, London borough, Unitary Authority, and Metropolitan District
Civil Parish and the Inner and Middle Temples
Electoral Division
Ward
Unitary Authority
Community
Electoral Division
Unitary Authority
Ward
Boundary Posts
Boundary Stones
Boundary Markers
Alignments of Boundaries
Textual Descriptions of Boundaries, Mereings and Posts and Stones
Where two or more boundaries are coincidental, a single alignment is shown by the most important boundary in the following order:
County, City and County of London, Unitary Authority, District, London Borough and Metropolitan District, Civil Parish, Community, Inner and Middle Temples
European Electoral Regions, County / Borough Constituencies
Welsh Assembly Electoral Region
Electoral Division and / or Ward
Unitary Authority
European Electoral Regions, County / Burgh Constituencies
Scottish Parliamentary Electoral Region
Ward
A textual description often accompanies this occurrence and is used for clarification. If the alignment of an administrative boundary coincides with any other feature (other than another boundary), then both will be shown in their respective themes.
More information on administrative boundary alignments can be found here.
Buildings are defined as permanent roofed constructions, usually with walls. This includes permanent roofed constructions that exceed 8.0m² in area (12.0m² in private gardens). Exceptions are made to this area rule for smaller buildings that, due to their detached position, form relatively important topographic features; these are shown at minimum size, as stated above. With a few exceptions (for example, by describing government offices or hypermarkets), no distinction is currently made between residential, private, public, commercial, or industrial buildings.
Physical features shown in the Buildings theme include:
Roofed Buildings (identified as being of sufficient size or importance to be shown)
Mobile or Park Homes that are permanent, residential and have a postal address
Archways and Covered Passageways, where the alignment can be determined from outside the building
Horticultural Glasshouses over 50m²
Covered Tanks
Features such as cooling towers, uncovered tanks, bridges, and monuments are shown within the Structures theme.
Only glasshouses over 50m² that serve a horticultural purpose will continue to be captured as glass structures. Other glass structures, such as office buildings and conservatories, exist within OS MasterMap and will be recorded as buildings. There are some non-physical features shown in the Buildings theme, represented as the following text features:
House Numbers
Descriptive Building Names
Distinctive Building Names
Detail in private gardens attached to residential buildings, such as sheds, pathways and ornamental ponds, is not captured as part of the specification. Where possible, all gardens of this type are generalised and represented by a single garden polygon.
For Ordnance Survey purposes, antiquities are defined as existing artificial features of a date not later than AD 1714 (the date of the accession of George I). These antiquities are captured along with very important battlefield sites and natural features connected with important historic events. Features and sites of a date later than AD 1714 may be treated as antiquities as an exception if they are of national importance.
The investigation, recording and surveying of archaeology is the responsibility of English Heritage, Historical Environment Scotland (HES) and Cadw (Wales). Antiquity find sites are not shown in OS MasterMap Topography Layer. Ordnance Survey has no responsibility for defining the authenticity of distinctive or descriptive names of antiquities.
Due to the variety of physical features in the Heritage and Antiquities theme, an exhaustive list is not provided, but the following are included:
Standing Stones
Earthworks
Hill Figures
Ruined Buildings
Tombs
Stone Circles
Some non-physical features are shown in the Heritage and Antiquity theme, including:
Textual Descriptions for the real-world objects
Battle Sites, as either text or a symbol
There are some limitations on what can be shown, imposed by survey principles. Many earthworks are of low relief and do not meet Ordnance Survey’s minimum criteria. To depict the feature clearly, it may be necessary to exaggerate antiquity detail. In mountain and moorland areas, some antiquity features may be generalised, without losing the essential characteristics of the depiction.
For Ordnance Survey purposes, a road is defined as a metalled way for vehicles. Roads that form part of the public network and driveways to private properties that are over 100m in length are normally included within OS MasterMap Topography Layer.
A track, for Ordnance Survey purposes, is defined as an unmetalled way that is clearly marked, permanent and used by vehicles. Tracks are only normally recorded in private gardens if they are 100m or more in length. They need not be ‘all weather’. All tracks are described as ‘Track’, or ‘Tk’ if required to be abbreviated. Distinctively named tracks have their name recorded, for example, HICKS LANE (Track).
For Ordnance Survey purposes, a path is defined as any established way other than a road or track. They can be considered as either ‘made’ or ‘unmade’.
Made paths are those whose surface is paved or metalled. Only major paths are shown in parks, public gardens, cemeteries and so on. Made paths are described by the annotation ‘Path’, except in built-up areas, where the description will not normally be recorded. Distinctive names, such as ‘Simmons Walk’, are also included as part of OS MasterMap Topography Layer.
Unmade paths are those that are neither paved nor metalled. An unmade path is included in OS MasterMap Topography Layer when its entire length is evident on the ground and it starts at a road, track or path and finishes at a similar feature or a specific place of interest. Unmade paths are described by the annotation 'Path (um)' in urban and rural areas.
Physical features shown in the Roads, Tracks and Paths theme are listed below:
Carriageway Limits, including any hard shoulder or shallow drainage gullies forming the side of the road on dual carriageways or motorways
Kerbed Roundabouts
Traffic Islands in roads (usually 8m² or more)
Traffic-calming measures forming a physical obstruction, including pinch points
Dedicated Cycle Lanes
Fords
Car Parks
Edges or centre alignments of tracks and paths
Step treads
Mile Posts
Guideposts (traditional fingerposts only)
Kerb Barriers
Gates across roads
Posts preventing vehicular access
Weighbridges
Cattle Grids
Hedges, Walls, Fences, and Banks
Crash Barriers (where they form the sole bounding feature of a carriageway)
Non-physical features shown in this theme are represented as distinctive and descriptive text and inferred links.
There are two situations where constraints on how the features are depicted are normally imposed by survey tolerances:
Where the central alignment of an unmade path is less than 1m (urban areas) or 2m (rural and moorland) from an adjacent building, fence, hedge or wall, the central alignment is shown at that minimum distance away from the feature.
Where one edge of a track is parallel and close to the bank of a water feature, the track edge nearest to the river is omitted.
It is important to note that rights of way are not identified in OS MasterMap Topography Layer. The representation of a road, track or path cannot be used as evidence of a right of way.
Information about the change history of a feature that comprises the reason for the change (reasonForChange attribute) and the date for this change (changeDate attribute). Each feature may have numerous change history records and these are ordered chronologically in the attribute. This attribute is present in all six feature types.
The reason for a change made to a feature. Forms part of the feature’s complex attribute, changeHistory.
Attribute Name: reasonForChange
Type: String
Multiplicity: [1]
The date a change was made to the feature by an editor. Forms part of the feature’s complex attribute, changeHistory.
This may not match the versionDate attribute.
Attribute Name: changeDate
Type: String
Multiplicity: [1]
Rail features are defined as features related to travel by railway or tramway. The exception to this is railway tunnels, which are currently in the Structures theme. OS MasterMap Topography Layer contains information relating to permanent railways that form the network between two points, for example, from railway station to railway station, or from an industrial building to a private quarry.
Standard-gauge railways are shown to scale by a pair of rails and represent tracks 1.435m apart. Railways narrower than 1.435m are deemed to be narrow gauge and are shown by a single line representing the central alignment. Tramways, metros, and light-rapid-transit systems are treated as railways.
Underground portions of the Metropolitan and District lines in London that are close to surface level are shown; where a deep-level tube railway comes to the surface and continues as a normal railway, it is shown as a standard-gauge railway. In other cities, only the sections of underground railways that are open to the sky are currently shown.
Physical features shown in the Rail theme include:
Level Crossings
Lighting Towers
Loading Gauges
Turntables
Mile or Kilometre Posts and Stones
Sand Drags
Signal Posts, Bridges, and Gantries
Switches and Slips
Retarders
Bridges and Viaducts
Mail Pick-ups
Rails
Permanent Ways
Station Buildings and Platforms
Some physical features are not shown in the Rail theme:
Telephones associated with Level Crossings
Conductor Rails and Overhead wires for electrified trains
Detail beneath the roofs of Railway Stations
Water Troughs
Repetitive Features, such as signal lights within marshalling yards
Some non-physical features are shown in the Rail theme: these are text descriptions of railway and associated railway features.
This contains information about the height above Ordnance Datum Newlyn (ODN; heightAboveDatum attribute) and, where known, the accuracy of this value (accuracyOfHeightAboveDatum attribute). This attribute is only present in the Topographic Line and the Topographic Point Feature Types.
The height of the feature above the ODN vertical datum, in metres. Forms part of the heightAboveDatum complex attribute.
Attribute Name: heightAboveDatum
Type: Real
Multiplicity: [1]
The accuracy of the vertical position in metres at the 95% confidence level. Forms part of the heightAboveDatum complex attribute.
Attribute Name: accuracyOfHeightAboveDatum
Type: String
Multiplicity: [1]
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<circle r=‘0.05’ cx=‘0’ cy=‘0.0’/> |
<circle r=‘0.375’ cx=‘0’ cy=‘0’/> |
Arc geometry: <polyline points=‘0,1.45 0,-1.55’ /> <path d=‘M-1.3,-0.95a2 2 0 0 1 1.3 1.05a2 2 0 0 1 1.3 -1.05’ /> <path d=‘M-0.9,0.3a2 2 0 0 1 0.9 0.85a2 2 0 0 1 0.9 -0.85’ />
Linear geometry: <polyline points=‘0.000,1.45 0.000,-1.55’/> <polyline points=‘-1.303,-0.970 -1.168,-0.927 -1.037,-0.874 -0.909,-0.814 -0.785,-0.746 -0.666,-0.670 -0.552,-0.586 -0.444,-0.496 -0.342,-0.398 -0.246,-0.295 -0.156,-0.185 -0.074,-0.070 0.000,0.050 0.074,-0.070 0.156,-0.185 0.246,-0.295 0.342,-0.398 0.444,-0.496 0.552,-0.586 0.666,-0.670 0.785,-0.746 0.909,-0.814 1.037,-0.874 1.168,-0.927 1.303,-0.970’/> <polyline points=‘-0.890,0.296 -0.769,0.364 -0.652,0.440 -0.541,0.523 -0.435,0.613 -0.335,0.709 -0.241,0.811 -0.154,0.919 -0.073,1.032 0.000,1.150 0.072,1.034 0.151,0.923 0.236,0.816 0.328,0.715 0.427,0.620 0.530,0.531 0.639,0.449 0.753,0.374 0.871,0.306’/> |
<polyline points=‘0.000,-0.775 0.000,0.775’/> <polyline points=‘-0.775,0.000 0.775,0.000’/> |
Arc geometry: <path d=‘M0,-1.6L-0.2,-0.8a0.6 0.6 0 1 0 -0.8 0.86a0.55 0.55 0 0 0 0.45 0.89a0.56 0.56 0 0 0 1.1 -0.0a0.55 0.55 0 0 0 0.45 -0.89a0.6 0.6 0 1 0 -0.8 -0.86L0,-1.6z’ /> Linear geometry: <polyline points=‘-1.074,0.097 -1.210,-0.031 -1.299,-0.194 -1.334,-0.377 -1.312,-0.561 - 1.233,-0.730 -1.106,-0.866 -0.944,-0.957 -0.761,-0.993 -0.576,-0.972 -0.407,-0.894 -0.270,- 0.768 -0.269,-0.765 -0.068,-1.539 0.012,-1.539 0.193,-0.756 0.193,-0.756 0.329,-0.887 0.499,-0.969 0.685,-0.993 0.870,-0.959 1.036,-0.869 1.164,-0.731 1.244,-0.561 1.267,-0.374 1.230,-0.189 1.138,-0.025 0.999,0.102 1.087,0.259 1.119,0.436 1.094,0.615 1.012,0.775 0.883,0.901 0.720,0.979 0.541,1.000 0.541,1.000 0.464,1.184 0.331,1.331 0.156,1.427 - 0.040,1.461 -0.236,1.427 -0.411,1.331 -0.544,1.184 -0.621,1.000 -0.801,0.978 -0.964,0.900 - 1.093,0.773 -1.175,0.611 -1.199,0.431 -1.164,0.254 -1.074,0.097’/> |
Style: stroke:#666666;fill:none;stroke-width:0.087
Geometry: See boulderGeometry in Shared symbol geometry above. |
Style: stroke:#669966;fill:none;stroke-width:0.087
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Style: stroke:#669966;fill:none;stroke-width:0.087
Geometry: See coniferousTreeGeometry in Shared symbol geometry above. |
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Geometry: See circleFillGeometry in Shared symbol geometry above. |
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Style: stroke:#669966;fill:669966;stroke-width:0.087 Geometry: See circleFillGeometry in Shared symbol geometry above. |
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Geometry: See nonconiferousTreeGeometry in Shared symbol geometry above. |
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Style: stroke:#0099ff; fill:none; stroke-width:0.087
Geometry: See crossGeometry in Shared symbol geometry above. |
Style: stroke:#000000;fill:none;stroke-width:0.087
Geometry: <polyline points=‘0.707,0.707 0.0,0.0 0.707,-0.707’/> <line x1=‘1.42’ y1=‘0.0’ x2=‘0.0’ y2=‘0.0’/> |
Style: stroke:#ff00ff;fill:none;stroke-width:0.087
Geometry: <circle r=‘0.625’ cx=‘2.875’ cy=‘0.0’/> <line x1=‘0.0’ y1=‘0.0’ x2=‘2.25’ y2=‘0.0’/> |
Style: stroke:#ff00ff;fill:none;stroke-width:0.087
Geometry: See circleGeometry in Shared symbol geometry above. |
Style: stroke:#0099ff;stroke-width:0.087
Geometry: <polyline points=‘-0.5,0 0.5,0’/> |
Style: stroke:#0099ff;fill:none;stroke-width:0.087
Geometry: <polyline points=`0.0,0.0 3.438,0.0’ /> <polyline points=‘0.5,0.5 0.0,0.0 0.5,-0.5’ /> <polyline points=‘3.35,0.5 2.85,0.0 3.35,-0.5’ /> <polyline points=‘3.938,0.5 3.438,0.0 3.938,-0.5’ /> |
Style: stroke:#000000;fill:none;stroke-width:0.087
Geometry: <polyline points=‘-2.25,0.0 2.25,0’/> <polyline points=‘0.0,-2.25 0.0,2.25’/> <circle r=‘0.625’ cx=‘0’ cy=‘2.875’/> <circle r=‘0.625’ cx=‘0’ cy=‘-2.875’/> <circle r=‘0.625’ cx=‘2.875’ cy=‘0’/> <circle r=‘0.625’ cx=‘-2.875’ cy=‘0’/> |
Style: stroke:#666666;fill:none;stroke-width:0.087
Geometry: See circleGeometry in Shared symbol geometry above. |
Style: stroke:#000000;fill:#000000;stroke-width:0.087
Geometry: See circleGeometry in Shared symbol geometry above. |
Style: stroke:#666666;fill:none;stroke-width:0.087
Geometry: See boulderGeometry in Shared symbol geometry above. |
Style: stroke:#666666;fill:none;stroke-width:0.087
Geometry: See coniferousTreeGeometry in Shared symbol geometry above. |
Style: stroke:#666666;fill:none;stroke-width:0.087
Geometry: See nonconiferousTreeGeometry in Shared symbol geometry above. |
Style: stroke:#000000;stroke-width:0.087
Geometry: <polyline points=‘-0.72,0 0.72,0’/> |
Style: stroke:#000000;fill:none;stroke-width:0.087
Geometry: <polyline points=‘0.707,0.707 0.0,0.0 0.707,-0.707’/> <line x1=‘2.42’ y1=‘0.0’ x2=‘0.0’ y2=‘0.0’/> |
Style: stroke:#ff0000; fill:none; stroke-width:0.087
Geometry: See crossGeometry in Shared symbol geometry above. |
Style: stroke:#000000;stroke-width:0.087
Geometry: <polyline style=‘fill:none’ points=‘0,-0.794 -1.375,-0.794 0.0,1.588 1.375,-0.794 0,-0.794’/> <circle style=‘fill:#000000’ r=‘0.0875’ cx=‘0’ cy=‘0.0’/> |
Style: stroke:#0099ff;fill:#0099ff;stroke-width:0.087
Geometry: See circleGeometry in Shared symbol geometry above. |
This technical specification provides detailed technical information about OS MasterMap Topography Layer. It is targeted at technical users and software developers.
OS MasterMap Topography Layer provides the most detailed and accurate large-scale representation of Great Britain available from Ordnance Survey. It contains features that represent objects in the physical environment, such as buildings, fields, fences, and letter boxes. It also includes intangible objects, such as county boundaries and the lines of mean high or low waters. There are over 500 million features in the product. Coverage includes the whole of Great Britain (i.e. England, Scotland, and Wales).
The three key concepts underlying OS MasterMap Topography Layer are:
A feature model with identifiable and persistent features.
Feature lifecycles defined to match actual change.
Integration of the OS MasterMap suite of products.
OS MasterMap Topography Layer is created on the premise of a feature-based model. This models the real world at the level of the feature, which represents an object in the real world. Each feature has an identity, location and other additional attribution.
The features that comprise OS MasterMap Topography Layer are managed by feature lifecycle rules. These rules manage how changes in real-world objects are represented by the features in OS MasterMap Topography Layer. The rules define what real-world change constitutes a modification to an existing feature, and what change is represented by a new feature. This management allows a consistent representation of changes in the real world, based upon the capture specification.
The suite of layers that make up OS MasterMap have been modelled to allow simple integration with each other. All the layers are managed in a single capture and maintenance environment, meaning the geometries of the different layers are in sympathy with each other, allowing easy integration. Additionally, they all invoke the principle of the Topographic Object Identifier (TOID) and use this as their unique IDs.
OS MasterMap layers include the following products: OS MasterMap Topography Layer, OS MasterMap Sites Layer, OS MasterMap Building Height Attribute, OS MasterMap Greenspace Layer, OS MasterMap Highways Network – Roads, OS MasterMap Highways Network – Routing and Asset Management Information (RAMI), OS MasterMap Highways Network – Paths, and OS MasterMap Water Network Layer.
OS MasterMap Topography Layer is available the following formats:
GeoPackage (area of interest – AOI – only)
Vector tiles (MBTiles)
Geography Markup Language (GML) 2.1.2
The data structure in this document is described by means of Unified Modeling Language (UML) class diagrams and accompanying tables containing text.
The following colour conventions have been used in the UML diagrams and tables: feature types from the Ordnance Survey product specification are orange, data types are in purple, and enumerations are green.
ISO 19115 compliant UK GEMINI discovery level metadata is provided for the data and can be found in the OS Data Catalogue.
OS MasterMap Topography Layer is comprised of nine themes:
The following sub-sections describe the main features and content of each theme in detail. This will aid users’ understanding of which features they can find in the data and the most likely theme(s) that the feature will be found in. The rules governing which theme or themes are assigned to a feature are discussed in theme rules.
Wherever possible, real-world objects are represented in their true surveyed position. However, for the sake of clarity of display or plotting, real-world objects may be generalised. For example, parallel features and small juts in house fronts may not be shown. The normal methods of generalisation that can be applied to features are:
Emphasis
Selection for inclusion
Simplification
Omission
Real-world objects may also be simplified in OS MasterMap Topography Layer, for example, a small group of trees may be recorded as a single point or polygon feature. The following sub-sections give a breakdown, by feature type, of the themes in greater detail, including regional and cultural special designations.
There are several rules that govern what theme or themes are assigned to a feature. These rules give the data consistency so that the same kind of real-world objects are assigned to the same themes as far as possible.
There is one attribute – called the descriptive group attribute – that has a major bearing on the theme rules. The value in the descriptive group is the key determinant of which theme(s) is / are assigned to a feature. The table below relates the value of descriptive group (of which there are 21) to the theme. If the feature has the value listed in the first column, it will be assigned into the theme listed in the second column.
There are some additional rules for assigning lines to themes. Lines serve two purposes in OS MasterMap Topography Layer. There are lines that are coincident with the boundaries of polygon features; these are called bounding lines and they are the most common type of line. However, some lines do not form boundaries to features, but are a feature in their own right; these are called non-bounding line features.
In addition to being a member of each theme rule, a line feature that is part of the boundary of one or more polygon features is also considered a member of the theme of those polygon features which it bounds. For example, any line feature that bounds a polygon feature that is a member of the Roads, Tracks and Paths theme is also a member of the Roads, Tracks and Paths theme, in addition to any other themes to which it belongs. The image below gives examples of the application of theme rules:
The product themes pages discuss the themes of OS MasterMap Topography Layer and outline the contents of each theme and explain how Ordnance Survey allocates a feature to one or more themes. This helps users to understand which theme a feature is likely to be found in, and why some features may appear in a theme that may not seem logical on first appearance.
Water features are defined as features that contain, delimit, or relate to real-world objects containing water.
Mean High Water (springs) and Mean Low Water (springs)
Swimming Pools, Ponds, Lakes, and Lochs
Moats, Bridges, and Footbridges
Reservoirs, Rivers, Canals, and Streams
Drains and Ditches
Foreshore Features
Floating Objects (they are only shown when they are fixed and attached to permanent detail)
Shake Holes and Swallow Holes (in mountain and moorland areas; limits of numerous shake holes are shown, and the area described as ‘area of shake holes’)
Sluices (except those found in sewage works) and Culverts
Stepping Stones
Taps (which take the form of drinking fountains or that form the communal water supply), Drinking Fountains and Water Troughs (public)
Tidal Gauges
Waterfalls (only if formed by natural features) and Weirs
Bollards, Capstans, and Mooring Posts
Breakwaters and Groynes
Perches, Pilot Beacons, and Navigational Beacons
Pumps, Wells, Spouts, Springs, and Fountains
Taps, water troughs and drinking fountains are no longer captured under the current specification.
The image below shows a sample of real-world objects in the Water theme, including a pond, a river, flow arrows, sluices, and drains:
Non-physical features shown in the Water theme are:
The highest point in a river to which normal tides flow; this is described as the Normal Tidal Limit (NTL). The point is shown and annotated with text.
Low Water Level (LWL); this is the point to which mean tides (or mean spring tides in Scotland) flow at low water. The point is shown and annotated with text.
Textual descriptions of all water features.
Flow arrows, which are symbols used to indicate the direction of flow of non-tidal moving water.
As water is a dynamic element within the landscape, certain survey principles and constraints are imposed on the representation of water within OS MasterMap Topography Layer.
Rivers, streams, and drains are shown at their true scale width. A single line is normally used where their width is less than:
1.0m in urban areas
2.0m in rural, mountain and moorland areas
OS MasterMap Topography Layer does not contain polygons of the open sea. Where inland water bodies meet the sea, the following principles are applied:
Ordnance Survey shows high and low water marks of a mean average tide, that is, an average tide halfway between spring and neap tides in England and Wales, and of average spring tides in Scotland.
In tidal rivers, the point to which mean tides (or spring tides in Scotland) flow at high or low water is included.
Lakes and ponds are surveyed at normal winter level; reservoirs are shown at top water level, that is, spill over level. All water features are described. Continuous topographical water features that extend into private gardens are shown. Where a river flows under another object, typically a bridge, the part of the river beneath the object is not supplied. This is why there are gaps in rivers when the theme is viewed on its own. An example of such a gap in a river is shown below:
Features providing information on symbols used when rendering OS MasterMap Topography Layer graphically (for example, Culvert).
Spatial attribute: point
Data type attribute: GM_Point
The unique topographic reference number. It consists of the letters ‘osgb’ followed by thirteen or sixteen digits. The TOID must always be retained / stored in its entirety and any leading zeros on the TOID are retained to permit linking of the feature to other OS MasterMap products.
Attribute Name: TOID or gml:id
Type: String
Multiplicity: [1]
Topographic features have a numerical feature code (a five-digit integer) assigned to each feature. This feature code is wholly determined by the feature type, the descriptive group(s) and the descriptive term(s). The feature code does not add any information to that contained in these attributes. The physicalLevel, physicalPresence and Make attributes do not affect the feature code.
The feature code itself is arbitrarily assigned and is therefore not informative without the look-up table that gives the feature type and attribute values corresponding to each feature code.
Attribute Name: featureCode (GML), feature_code (GeoPackage), N/A (Vector Tiles)
Type: Integer
Multiplicity: [0..1]
The version number of the feature (in the range of 1 to 4294967295). This uniquely identifies a specific version of a feature with a given TOID.
Attribute Name: version (GML), Version (GeoPackage), N/A (Vector Tiles)
Type: Integer
Multiplicity: [0..1]
The date on which this version of the feature became the current version. This is the date on which the feature was changed in the database and is not the date of any associated real-world change.
Attribute Name: versionDate (GML), version_date (GeoPackage), N/A (Vector Tiles)
Type: Date
Multiplicity: [1]
A theme that the feature belongs to.
Attribute Name: theme (GML), Theme (GeoPackage), theme (Vector Tiles)
Multiplicity: [1..*]
Information about the change history of a feature that comprises the reason for the change and the date for this change. Each feature may have numerous change history records, and these are ordered chronologically. A complex attribute.
Attribute Name: changeHistory
Multiplicity: [1..*]
This is the primary classification attribute of a feature.
It assigns a feature to one or more of 21 groups, most of which are categories of real-world topographic objects, such as path, building or natural environment; others are categories of supportive or administrative features, such as network or polygon closing geometry and political or administrative. In general, values of this attribute are not specific to particular feature types.
Attribute Name: descriptiveGroup (GML), descriptive_group (GeoPackage), N/A (Vector Tiles)
Multiplicity: [1..*]
This attribute, if present, gives further classification information about the feature. A feature may have multiple descriptiveTerm attributes, but this is little used at present. Most features have zero or one descriptiveTerm attributes.
Attribute Name: descriptiveTerm (GML), descriptive_term (GeoPackage), N/A (Vector Tiles)
Multiplicity: [0..*]
The orientation of symbol features for cartographic placement. Given in tenths of a degree anticlockwise from due east (0–3599).
Attribute Name: orientation (GML), Orientation (GeoPackage), orientation (Vector Tiles)
Type: Integer
Multiplicity: [1]
This attribute states whether the feature is underground, obscured below normal cartographic level, at normal cartographic level, or overhead.
Normal cartographic level is that perceived to be the normal surface level. Where an area feature overlies others (for example, bridges), they are at normal cartographic level and the features below them are recorded as obscured.
Attribute Name: physicalLevel (GML), physical_level (GeoPackage), N/A (Vector Tiles)
Type: Integer
Multiplicity: [1]
This attribute indicates the nature of the object represented by the feature. This is normally used for TopographicLine, for example, a value of ‘obstructing’ indicates that the feature prevents pedestrian access, whereas a value of ‘edge/limit’ means that the feature represents a change of surface type and does not generally impede access. This attribute is also used to identify administrative boundary and inferred line features, and moveable area features (for example, moveable cranes).
Attribute Name: physicalPresence (GML), physical_presence (GeoPackage), N/A (Vector Tiles)
Multiplicity: [0..1]
A pair of easting and northing ordinates in metres, defining a horizontal location in the British National Grid spatial reference system.
Attribute Name: point
Type: GM_Point
Multiplicity: [1]
A reference by TOID to a related feature. In cartographic symbol features, it is used to point from the symbol feature to the topographic feature to which it refers.
ReferenceToFeature is only used for culverts, and, in that case, it is singular and mandatory.
Attribute Name: N/A (GML), reference_to_feature (GeoPackage), N/A (Vector Tiles)
Type: String
Multiplicity: [1]
Feature representing topographic objects and concepts that have a line-based geometry (for example, Fence).
Spatial attribute: polyline
Data type attribute: GM_Curve or GM_MultiCurve
The unique topographic reference number. It consists of the letters ‘osgb’ followed by thirteen or sixteen digits. The TOID must always be retained/stored in its entirety and any leading zeros on the TOID are retained to permit linking of the feature to other OS MasterMap products.
Attribute Name: TOID or gml:id
Type: String
Multiplicity: [1]
Topographic features have a numerical feature code (a five-digit integer) assigned to each feature. This feature code is wholly determined by the feature type, the descriptive group(s) and the descriptive term(s). The feature code does not add any information to that contained in these attributes. The physicalLevel, physicalPresence and make attributes do not affect the feature code.
The feature code itself is arbitrarily assigned and is therefore not informative without the look-up table that gives the feature type and attribute values corresponding to each feature code.
Attribute Name: featureCode (GML), feature_code (GeoPackage), N/A (Vector Tiles)
Type: Integer
Multiplicity: [1]
The version number of the feature (in the range 1 to 4294967295). This uniquely identifies a specific version of a feature with a given TOID.
Attribute Name: version (GML), version (GeoPackage), N/A (Vector Tiles)
Type: Integer
Multiplicity: [0..1]
The date on which this version of the feature became the current version. This is the date on which the feature was changed in the database and is not the date of any associated real-world change.
Attribute Name: versionDate (GML), version_date (GeoPackage), N/A (Vector Tiles)
Type: Date
Multiplicity: [1]
A theme that the feature belongs to.
Attribute Name: theme (GML), theme (GeoPackage), N/A (Vector Tiles)
Multiplicity: [1..*]
The accuracy of a horizontal position in metres at the 95% confidence level.
Attribute Name: accuracyOfPosition (GML), accuracy_of_position (GeoPackage), N/A (Vector Tiles)
Multiplicity: [1]
Information about the change history of a feature that comprises the reason for the change and the date for this change. Each feature may have numerous change history records, and these are ordered chronologically. A complex attribute.
Attribute Name: changeHistory
Multiplicity: [1..*]
This is the primary classification attribute of a feature.
It assigns a feature to one or more of 21 groups, most of which are categories of real-world topographic objects, such as path, building or natural environment; others are categories of supportive or administrative features, such as network or polygon closing geometry and political or administrative. In general, values of this attribute are not specific to particular feature types.
Due to limitations in the source data from which OS MasterMap was created, there are some exceptions to this principle. For instance, the descriptiveGroup buildings or structure contains text describing or naming buildings and structures, while the topographic features have the descriptiveGroup values of building, glasshouse or structures.
Attribute Name: descriptiveGroup (GML), descriptive_group (GeoPackage), N/A (Vector Tiles)
Multiplicity: [1..*]
This attribute, if present, gives further classification information about the feature.
A feature may have multiple descriptiveTerm attributes. Most features have zero or one descriptiveTerm attributes. A situation where multiple descriptiveTerm attributes are used is where line features have a descriptiveGroup with the value of ‘Tidal Water’. These features may have multiple descriptiveTerm attributes, for example, where Mean High Water (Springs) and Mean Low Water (Springs) are co-incident.
Attribute Name: descriptiveTerm (GML), descriptive_term (GeoPackage), N/A (Vector Tiles)
Multiplicity: [0..*]
Indicates that a TopographicLine feature is not on the boundary of a TopographicArea feature.
Attribute Name: nonBoundingLine (GML), non_bounding_line (GeoPackage), N/A (Vector Tiles)
Type: Boolean
Multiplicity: [0..1]
A complex attribute that is comprised of two simple attributes. The height of the feature above the Ordnance Datum Newlyn (ODN) vertical datum (in metres) is defined in the ‘heightAboveDatum’ attribute. The accuracy of the vertical position in metres at the 95% confidence level is defined by the ‘accuracyOfHeightAboveDatum’ attribute.
Attribute Name: heightAboveDatum (GML), height_above_datum (GeoPackage), N/A (Vector Tiles)
Multiplicity: [0..1]
A complex attribute that is comprised of two simple attributes. The height of the feature above ground level (in metres) is defined in the ‘heightAboveGroundLevel’ attribute. The accuracy of the vertical position in metres at the 95% confidence level is defined by the ‘accuracyOfHeightAboveGroundLevel’ attribute.
Attribute Name: heightAboveGroundLevel (GML), height_above_ground_level (GeoPackage), N/A (Vector Tiles)
Multiplicity: [0..1]
Where known, indicates whether the real-world nature of the feature is man-made or natural.
Attribute Name: make (GML), make (GeoPackage), make (Vector Tiles)
Multiplicity: [0..1]
This attribute states whether the feature is underground, obscured below normal cartographic level, at normal cartographic level, or overhead.
Normal cartographic level is that perceived to be the normal surface level. Where an area feature overlies another (for example, bridges), they are at normal cartographic level and the features below them are recorded as obscured.
Indicates the physical level of a feature with reference to the normal cartographic surface level. Only four values are used:
-1 = Underground detail 49 = Obscured detail below the normal cartographic level 50 = Detail at the normal cartographic level 51 = Overhead detail above normal cartographic level
Attribute Name: physicalLevel (GML), physical_level (GeoPackage), N/A (Vector Tiles)
Type: Integer
Multiplicity: [1]
This attribute indicates the nature of the object represented by the feature. This is normally used for TopographicLine, for example, a value of ‘obstructing’ indicates that the feature prevents pedestrian access, whereas a value of ‘edge/limit’ means that the feature represents a change of surface type and does not generally impede access. This attribute is also used to identify administrative boundary and inferred line features, and moveable area features (for example, moveable cranes).
Attribute Name: physicalPresence (GML), physical_presence (GeoPackage), N/A (Vector Tiles)
Multiplicity: [0..1]
This is either a Polyline or a Multiline geometry. In TopographicLine features, this will only be a Multiline if there is a problem with the geometry that is indicated by the broken metadata flag.
Attribute Name: polyline
Type: GM_MultiCurve
Multiplicity: [1]
Features that define the content and placement of text when rendering OS MasterMap graphically (for example, Road Name or Classification).
Spatial attribute: point
Data type attribute: GM_Point
The unique topographic reference number. It consists of the letters ‘osgb’ followed by thirteen or sixteen digits. The TOID must always be retained/stored in its entirety and any leading zeros on the TOID are retained to permit linking of the feature to other OS MasterMap products.
Attribute Name: TOID
Type: String
Multiplicity: [1]
Topographic features have a numerical feature code (a five-digit integer) assigned to each feature. This feature code is wholly determined by the feature type, the descriptive group(s) and the descriptive term(s). The feature code does not add any information to that contained in these attributes. The physicalLevel, physicalPresence and Make attributes do not affect the feature code.
The feature code itself is arbitrarily assigned and is therefore not informative without the look-up table that gives the feature type and attribute values corresponding to each feature code.
Attribute Name: featureCode (GML), feature_code (GeoPackage), N/A (Vector Tiles)
Type: Integer
Multiplicity: [0..1]
The version number of the feature (in the range of 1 to 4294967295). This uniquely identifies a specific version of a feature with a given TOID.
Attribute Name: version (GML), version (GeoPackage), N/A (Vector Tiles)
Type: Integer
Multiplicity: [0..1]
The date on which this version of the feature became the current version. This is the date on which the feature was changed in the database and is not the date of any associated real-world change.
Attribute Name: versionDate (GML), version_date (GeoPackage), N/A (Vector Tiles)
Type: Date
Multiplicity: [1]
A theme that the feature belongs to.
Attribute Name: theme (GML), theme (GeoPackage), theme (Vector Tiles)
Multiplicity: [1..*]
The coordinate position that a piece of text is positioned relative to. Measured in metres in the British National Grid spatial reference system.
Attribute Name: anchorPoint
Type: GM_Point
Multiplicity: [1]
Attribute Name: changeHistory
Multiplicity: [1..*]
This is the primary classification attribute of a feature. It assigns a feature to one or more of 21 groups, most of which are categories of real-world topographic objects, such as path, building or natural environment; others are categories of supportive or administrative features, such as network or polygon closing geometry and political or administrative. In general, values of this attribute are not specific to particular feature types.
Attribute Name: descriptiveGroup
Multiplicity: [0..*]
This attribute, if present, gives further classification information about the feature. A feature may have multiple descriptiveTerm attributes, but this is little used at present. Most features have zero or one descriptiveTerm attributes.
Attribute Name: descriptiveTerm (GML), descriptive_term (GeoPackage), N/A (Vector Tiles)
Multiplicity: [0..*]
Where known, indicates whether the real-world nature of the feature is man-made or natural.
Attribute Name: make (GML), make (GeoPackage), make (Vector Tiles)
Multiplicity: [0..1]
This attribute states whether the feature is underground, obscured below normal cartographic level, at normal cartographic level, or overhead.
Normal cartographic level is that perceived to be the normal surface level. Where an area feature overlies another (for example, bridges), they are at normal cartographic level and the features below them are recorded as obscured.
Attribute Name: physicalLevel (GML), physical_level (GeoPackage), N/A (Vector Tiles)
Type: Integer
Multiplicity: [1]
This attribute indicates the nature of the object represented by the feature. This is normally used for TopographicLine, for example, a value of ‘obstructing’ indicates that the feature prevents pedestrian access, whereas a value of ‘edge/limit’ means that the feature represents a change of surface type and does not generally impede access. This attribute is also used to identify administrative boundary and inferred line features, and moveable area features (for example, moveable cranes).
Attribute Name: physicalPresence (GML), physical_presence (GeoPackage), N/A (Vector Tiles)
Multiplicity: [0..1]
Provides the information to graphically display a text string in harmony with the underlying map detail and consists of anchorPosition, font, height and orientation. textRendering is a complex attribute.
Attribute Name: textRendering
Multiplicity: [1]
Textual information that can be rendered using the textRendering attribute.
Attribute Name: textString (GML), text_string (GeoPackage), text_string (Vector Tiles)
Type: String
Multiplicity: [1]
Features representing topographic objects that have a polygon-based geometry (for example, Building).
Spatial attribute: polygon
Data type attribute: GM_Surface
The unique topographic reference number. It consists of the letters ‘osgb’ followed by thirteen or sixteen digits. The TOID must always be retained/stored in its entirety and any leading zeros on the TOID are retained to permit linking of the feature to other OS MasterMap products.
Attribute Name: TOID or gml:id
Type: String
Multiplicity: [1]
Topographic features have a numerical feature code (a five-digit integer) assigned to each feature. This feature code is wholly determined by the feature type, the descriptive group(s) and the descriptive term(s). The feature code does not add any information to that contained in these attributes. The physicalLevel, physicalPresence and make attributes do not affect the feature code.
The feature code itself is arbitrarily assigned and is therefore not informative without the look-up table that gives the feature type and attribute values corresponding to each feature code.
Attribute Name: featureCode (GML), feature_code (GeoPackage), N/A (Vector Tiles)
Type: Integer
Multiplicity: [1]
The version number of the feature (in the range of 1 to 4294967295). This uniquely identifies a specific version of a feature with a given TOID.
Attribute Name: version (GML), Version (GeoPackage), N/A (Vector Tiles)
Type: Integer
Multiplicity: [0..1]
The date on which this version of the feature became the current version. This is the date on which the feature was changed in the database and is not the date of any associated real-world change.
Attribute Name: versionDate (GML), version_date (GeoPackage), N/A (Vector Tiles)
Type: Date
Multiplicity: [1]
A theme that the feature belongs to.
Attribute Name: theme (GML), Theme (GeoPackage), theme (Vector Tiles)
Multiplicity: [1..*]
This is the calculated area of a polygon feature in square metres.
Attribute Name: calculatedAreaValue (GML), calculated_area_value (GeoPackage), N/A (Vector Tiles)
Type: Measure
Multiplicity: [1]
Information about the change history of a feature that comprises the reason for the change and the date for this change. Each feature may have numerous change history records, and these are ordered chronologically. A complex attribute.
Attribute Name: changeHistory
Multiplicity: [1..*]
This is the primary classification attribute of a feature.
It assigns a feature to one or more of 21 groups, most of which are categories of real-world topographic objects, such as path, building or natural environment; others are categories of supportive or administrative features, such as network or polygon closing geometry and political or administrative. In general, values of this attribute are not specific to particular feature types.
Due to limitations in the source data from which OS MasterMap was created, there are some exceptions to this principle. For instance, the descriptiveGroup buildings or structure contains text describing or naming buildings and structures, while the topographic features have the descriptiveGroup values of building, glasshouse or structures.
Attribute Name: descriptiveGroup (GML), descriptive_group (GeoPackage), N/A (Vector Tiles)
Multiplicity: [1..*]
This attribute, if present, gives further classification information about the feature.
A feature may have multiple descriptiveTerm attributes, but this is little used at present. Most features have zero or one descriptiveTerm attributes. A situation where multiple descriptiveTerm attributes are used is where area features have a descriptiveGroup with the value of ‘Natural Environment’. These features can have one or more descriptiveTerm attributes specifying the natural land cover types present in the area.
Attribute Name: descriptiveTerm (GML), descriptive_term (GeoPackage), N/A (Vector Tiles)
Multiplicity: [0..*]
Where known, indicates whether the real-world nature of the feature is man-made or natural.
Attribute Name: make (GML), Make (GeoPackage), N/A (Vector Tiles)
Type: MakeValue
Multiplicity: [0..1]
This attribute states whether the feature is underground, obscured below normal cartographic level, at normal cartographic level, or overhead.
Normal cartographic level perceived to be the normal surface level. Where an area feature overlies another (for example, bridges), they are at normal cartographic level and the features below them are recorded as obscured.
Indicates the physical level of a feature with reference to the normal cartographic surface level. Only four values are used: -1 = Underground detail 49 = Obscured detail below the normal cartographic level 50 = Detail at the normal cartographic level 51 = Overhead detail above normal cartographic level
Attribute Name: physicalLevel (GML), physical_level (GeoPackage), N/A (Vector Tiles)
Type: Integer
Multiplicity: [1]
This attribute indicates the nature of the object represented by the feature. This is normally used for TopographicLine, for example, a value of ‘obstructing’ indicates that the feature prevents pedestrian access, whereas a value of ‘edge/limit’ means that the feature represents a change of surface type and does not generally impede access. This attribute is also used to identify administrative boundary and inferred line features, and moveable area features (for example, moveable cranes).
Attribute Name: physicalPresence (GML), physical_presence (GeoPackage), N/A (Vector Tiles)
Multiplicity: [0..1]
A polygon is a single closed region defined by a set of lines that represent the boundaries.
Attribute Name: polygon
Type: GM_Surface
Multiplicity: [1]
Features representing the boundaries of administrative areas that have a line-based geometry (for example, Parish Boundary).
Spatial attribute: polyline
Data type attribute: GM_MultiCurve
The unique topographic reference number. It consists of the letters ‘osgb’ followed by thirteen or sixteen digits. The TOID must always be retained / stored in its entirety and any leading zeros on the TOID are retained to permit linking of the feature to other OS MasterMap products.
Attribute Name: TOID or gml:id
Type: String
Multiplicity: [1]
Topographic features have a numerical feature code (a five-digit integer) assigned to each feature. This feature code is wholly determined by the feature type, the descriptive group(s) and the descriptive term(s). The feature code does not add any information to that contained in these attributes. The physicalLevel, physicalPresence and make attributes do not affect the feature code.
The feature code itself is arbitrarily assigned and is therefore not informative without the look-up table that gives the feature type and attribute values corresponding to each feature code.
Attribute Name: featureCode (GML), feature_code (GeoPackage), N/A (Vector Tiles)
Type: Integer
Multiplicity: [1]
The version number of the feature (in the range of 1 to 4294967295). This uniquely identifies a specific version of a feature with a given TOID.
Attribute Name: version (GML), version (GeoPackage), N/A (Vector Tiles)
Type: Integer
Multiplicity: [0..1]
The date on which this version of the feature became the current version. This is the date on which the feature was changed in the database and is not the date of any associated real-world change.
Attribute Name: versionDate (GML), version_date (GeoPackage), N/A (Vector Tiles)
Type: Date
Multiplicity: [1]
A theme that the feature belongs to.
Attribute Name: theme (GML), theme (GeoPackage), theme (Vector Tiles)
Multiplicity: [1..*]
The accuracy of a horizontal position in metres at the 95% confidence level.
Attribute Name: accuracyOfPosition (GML), accuracy_of_position (GeoPackage), N/A (Vector Tiles)
Multiplicity: [1]
Information about the change history of a feature that comprises the reason for the change and the date for this change. Each feature may have numerous change history records and these are ordered chronologically. A complex attribute.
Attribute Name: changeHistory
Multiplicity: [1..*]
This is the primary classification attribute of a feature.
It assigns a feature to one or more of 21 groups, most of which are categories of real-world topographic objects, such as path, building or natural environment; others are categories of supportive or administrative features, such as network or polygon closing geometry and political or administrative. In general, values of this attribute are not specific to particular feature types.
Due to limitations in the source data from which OS MasterMap was created, there are some exceptions to this principle. For instance, the descriptiveGroup buildings or structure contains text describing or naming buildings and structures, while the topographic features have the descriptiveGroup values of building, glasshouse or structures. NOTE: There is only ever one descriptiveGroup with the value of ‘Political Or Administrative’ on a BoundaryLine feature.
Attribute Name: descriptiveGroup (GML), descriptive_group (GeoPackage), N/A (Vector Tiles)
Multiplicity: [1]
This attribute, if present, gives further classification information about the feature.
A feature may have multiple descriptiveTerm attributes, but this is little used at present. Most features have zero or one descriptiveTerm attributes. A situation where multiple descriptiveTerm attributes are used is where area features have a descriptiveGroup with the value of ‘Natural Environment’. These features can have one or more descriptiveTerm attributes specifying the natural land cover types present in the area.
Attribute Name: descriptiveGroup (GML), descriptive_group (GeoPackage), N/A (Vector Tiles)
Multiplicity: [0..*]
This attribute states whether the feature is underground, obscured below normal cartographic level, at normal cartographic level, or overhead.
Normal cartographic level is that perceived to be the normal surface level. Where an area feature overlies another (for example, bridges), they are at normal cartographic level and the features below them are recorded as obscured.
Indicates the physical level of a feature with reference to the normal cartographic surface level. Only four values are used: -1 = Underground detail 49 = Obscured detail below the normal cartographic level 50 = Detail at the normal cartographic level 51 = Overhead detail above normal cartographic level
Attribute Name: physicalLevel (GML), physical_level (GeoPackage), N/A (Vector Tiles)
Type: Integer
Multiplicity: [1]
This attribute is also used to identify an administrative or political boundary.
Attribute Name: physicalPresence (GML), physical_presence (GeoPackage), N/A (Vector Tiles)
Multiplicity: [1]
A polyline is an ordered set of points forming a line feature.
Attribute Name: polyline
Type: GM_MultiCurve
Multiplicity: [1]
The symbols defined in Symbols and Compound symbols that end with the term FillSymbol are all used for pattern fills. The name of the pattern is taken from the symbol name by replacing FillSymbol with the term Pattern.
The exceptions to this principle are:
scatteredBouldersPattern uses smallBoulderFillSymbol
scatteredRocksPattern uses smallRockFillSymbol
scatteredConiferousTreesPattern uses smallConiferousTreeFillSymbol
scatteredNonconiferousTreesPattern uses smallNonconiferousTreeFillSymbol
To produce a particular pattern, the appropriate fill symbol is distributed on a grid that is repeated to cover the polygon being drawn. The sections below detail the grids that are currently in use.
Variables | Value/s |
---|---|
In this example, heathAndScrubPattern uses the natural environment grid to produce the pattern below:
This is then applied as a polygon fill:
Name | Attributes | Colour | Visual |
---|---|---|---|
The symbols defined in the Fill symbols section may be combined to form aggregated symbols. To do this, the coordinates of the original symbols are translated by a specified offset. Compound symbols may be used as components to make up other compound symbols.
For example, to define the scrub fill symbol, we combine the bushFillSymbol and smallBushFillSymbol using the following translations:
To define the mixed vegetation type of scrub and rough grass, the scrubFillSymbol created in the previous example is used in conjunction with roughGrassFillSymbol:
Offset:
Symbol 1 – translate(-1 0.3)
Symbol 2 – translate(1.75 -1)
Compound symbol | Fill symbols | Shape |
---|---|---|
Offset:
Symbol 1 – translate(-0.8 1)
Symbol 2 – translate(1.2 –1.2)
Offset:
Symbol 1 – translate(-1 -1)
Symbol 2 – translate(1 1)
Offset:
Symbol 1 – translate(-2 -2)
Symbol 2 – translate(-0.5 0.5)
Symbol 3 – translate(2 2)
Offset:
Symbol 1 – translate(0 -1)
Symbol 2 – translate(-2 1)
Symbol 3 – translate(2 1)
A land feature is defined as either a man-made or a natural polygon feature that describes the surface cover and area to which it is applied. This includes both natural and man-made slopes and cliffs. All general features are also placed in the Land theme. There are some exceptions to this, such as routes of communication and buildings.
Landform features, such as slopes and cliffs, behave slightly differently from other features as in the instances that they are represented as line features, they can cross other line features without being broken at the intersection of the line. Additionally, when they are polygon features, they can overlap other polygon features instead of sitting adjacent to them.
The Land theme encompasses those areas that do not form part of another theme. For example, a grass verge next to a road would appear in the Roads, Tracks, and Paths theme, whereas a grass area within a park would be in the Land theme.
The limits of geographic features such as hills and valleys are not recorded, although the distinctive names of these geographic features are shown when applicable.
Physical features shown in the Land theme include:
Recreation areas such as Parks, Playing Fields, Football Pitches, and Golf Courses
Slopes and Cliffs
Car Parks
Gardens
Woodlands
Areas of Vegetation (including scrub, heath, rough grass, and marshland) The Land theme also contains text features that describe the physical features.
In the image below, different types of vegetation cover have been identified on the edges of a settlement. Each type of vegetation has been labelled using the attribution within OS MasterMap Topography Layer:
This section defines the default styles for the presentation of new descriptive terms within OS MasterMap. This specifies the colours, symbols and line styles used for visual display and printing of OS MasterMap. The styles are defined using the Scalable Vector Graphics (SVG) syntax.
Ordnance Survey has chosen to use colours that are consistent in the internet environment. The particular colours used are defined with both their RGB and hexadecimal values in colour palette.
The colour palette for the new descriptive terms is listed in the table below
Image | Hex (r,g,b) | Style Name |
---|---|---|
Point symbols are used to represent the position of particular features within the data, such as a telephone call box or bollard. The symbol represents the location and type of feature.
Point symbols are applied to the visual representation by translating them to the location of the feature they are representing and rotating them, if the orientation attribute is present, by a given amount.
The additional point symbols for the new descriptive terms are listed below:
Symbol | Style and Geometry | Shape |
---|---|---|
Fill symbols are used to represent some attribution of a polygon feature and are distributed as a pattern fill across the polygon. For example, the symbol may represent information about the topographic surface such as the vegetation type.
The additional fill symbols for the new descriptive terms are listed below:
To produce a particular pattern, the appropriate fill symbol is distributed on a grid that is repeated to cover the polygon being drawn.
You can use the following grids with the new descriptive terms:
Small regular grid
Line styles are used to allow a user to distinguish between different types of linear feature, for example, distinctions may be made to emphasise:
Obstructing detail
Non-obstructing detail
Underground detail
Overhead detail
Building outlines
Water limits and linear features
Landform detail
Narrow-gauge railways
Statutory boundaries.
Polygon-closing features
The additional lines style for the new descriptive terms are listed below:
In OS MasterMap Topography Layer, features are classified using feature type and feature description attributes. This section describes the feature types and shows their permitted attribution. The tables below provide the following information about each feature type attribute:
The name of the attribute and what it is describing.
The nature of the attribute. The following values may occur:
Type | Description |
---|---|
[1] indicates that the attribute is mandatory and can only occur once. [1..*] indicates that the attribute is mandatory and can occur many times. [0..1] indicates that the attribute is optional; if present, it only occurs once.
[0..*] indicates that the attribute is optional; if present, it can occur many times.
The product is comprised of six feature types:
Three of these are topographic feature types: TopographicPoint (such as a post), TopographicLine (such as Mean High Water) and TopographicArea (such as coniferous trees)
One is a boundary feature type: BoundaryLine (such as unitary authority boundary)
Two are cartographic feature types: CartographicSymbol and CartographicText
In addition, if a Change-Only Update (COU) Supply has been provided, the data may contain information about the movement and deletion of features (i.e. Inserts, Updates and Deletes). These are represented by the feature type called DepartedFeature. More information about COU is contained in Section 10 – COU overview.
Each of the six feature types is discussed in more detail in their sub-pages.
Structures are defined as features that are man-made constructions but do not qualify as buildings
(for example, Band Stands and Clock Towers). These features may or may not obstruct passage at ground level. OS MasterMap Topography Layer contains information relating to all permanent structures that are considered large enough to be included. The image below gives some examples (highlighted in dark grey) of structures:
Stand-Alone Monuments
Fountains
Covered Reservoirs
Pylons
Weirs and Sluices
Gas Holders
Double Walls
Pontoons
Uncovered Tanks
Conveyors
Cooling Towers
Upper Levels of Communication
Bridges, Viaducts, Aqueducts, and Piers Non-physical features are represented by text.
These are features that denote the ground level at any given point. OS MasterMap Topography Layer does not contain height contours, instead it contains height information point features of known height.
These are physical marks that represent points in the national triangulation scheme. The best-known form is the triangulation pillar, often found on hill or mountain tops. Other forms include triangulation points placed on church towers and flagpoles. The coordinates of a triangulation station in the data are not usually the very accurate coordinates for the control point. The accurate coordinates of the control point can be obtained from Ordnance Survey (see sub-section below on spot height). All triangulation stations are shown, except for buried and surface blocks.
These are non-physical points, the altitude of which (relative to Ordnance Datum) has been determined by levelling. All current spot heights are shown by a point feature or symbol. The altitude to one decimal place of a metre is shown by a textual description. The latest information on Ordnance Survey’s GPS, triangulation and control points can be found on the .
Bench marks are represented in OS MasterMap Topography Layer as a symbol to mark their position. The values for these bench marks are available from the . It should be noted that the bench mark information is historic, and Ordnance Survey cannot guarantee its accuracy.
A complex attribute is an attribute that consists of two or more simple attributes that go together to convey some composite information about a feature. They only exist within the GML format.
Further information on complex attributes in OS MasterMap Topography Layer is detailed in the following sub-pages.
Features representing topographic objects and other concepts that have a point-based geometry (for example, Telephone Call Box).
Spatial attribute: point
Data type attribute: GM_Point
The unique topographic reference number consists of the letters ‘osgb’ followed by either thirteen or sixteen digits. The TOID must always be retained/stored in its entirety, and any leading zeros on the TOID are retained to permit linking of the feature to other OS MasterMap products.
Attribute Name: TOID or gml:id
Type: String
Multiplicity: [1]
Topographic features have a numerical feature code (a five-digit integer) assigned to each feature. This feature code is wholly determined by the feature type, the descriptive group(s) and the descriptive term(s). The feature code does not add any information to that contained in these attributes. The 'physicalLevel' attribute, 'physicalPresence' attribute and 'Make' attribute do not affect the feature code.
The feature code itself is arbitrarily assigned and is therefore not informative without the that gives the feature type and attribute values corresponding to each feature code.
Attribute Name: featureCode (GML), feature_code (GeoPackage), N/A (Vector Tiles)
Type: Integer
Multiplicity: [0..1]
The version number of the feature (in the range 1 to 4294967295). This uniquely identifies a specific version of a feature with a given TOID.
Attribute Name: version (GML), Version (GeoPackage), N/A (Vector Tiles)
Type: Integer
Multiplicity: [0..1]
The date on which this version of the feature became the current version. This is the date on which the feature was changed in the database and is not the date of any associated real-world change.
Attribute Name: versionDate (GML), version_date (GeoPackage), N/A (Vector Tiles)
Type: Date
Multiplicity: [1]
A theme that the feature belongs to.
Attribute Name: theme (GML), Theme (GeoPackage), theme (Vector Tiles)
Multiplicity: [1..*]
The accuracy of a horizontal position in metres at the 95% confidence level.
Attribute Name: accuracyOfPosition (GML), accuracy_of_position (GeoPackage), N/A (Vector Tiles)
Multiplicity: [1]
Information about the change history of a feature that comprises the reason for the change and the date for this change. Each feature may have numerous change history records, and these are ordered chronologically. A complex attribute.
Attribute Name: changeHistory
Multiplicity: [1..*]
This is the primary classification attribute of a feature.
It assigns a feature to one or more of 21 groups, most of which are categories of real-world topographic objects, such as path, building or natural environment; others are categories of supportive or administrative features, such as network or polygon closing geometry and political or administrative. In general, values of this attribute are not specific to particular feature types.
Due to limitations in the source data from which OS MasterMap Topography Layer was created, there are some exceptions to this principle. For instance, the descriptiveGroup buildings or structure contain text describing or naming buildings and structures, while the topographic features have the descriptiveGroup values of building, glasshouse or structures.
Attribute Name: descriptiveGroup (GML), descriptive_group (GeoPackage), N/A (Vector Tiles)
Multiplicity: [1..*]
This attribute, if present, gives further classification information about the feature.
A feature may have multiple descriptiveTerm attributes. Most features have zero or one descriptiveTerm attribute/s. Multiple descriptiveTerm attributes occur in several different scenarios, such as where point features have a descriptiveGroup with the value of ‘Structure’ or ‘Inland Water’. These features can have one or more descriptiveTerm attributes specifying the type of feature shown by the point.
Attribute Name: descriptiveTerm (GML), descriptive_term (GeoPackage), N/A (Vector Tiles)
Multiplicity: [0..*]
A complex attribute that is comprised of two simple attributes. The height of the feature above the Ordnance Datum Newlyn (ODN) vertical datum (in metres) is defined in the ‘heightAboveDatum’ attribute The accuracy of the vertical position in metres at the 95% confidence level is defined by the ‘accuracyOfHeightAboveDatum’ attribute.
Attribute Name: heightAboveDatum (GML), height_above_datum (GeoPackage), N/A (Vector Tiles)
Multiplicity: [0..1]
A complex attribute that is comprised of two simple attributes. The height of the feature above ground level (in metres) is defined in the ‘heightAboveGroundLevel’ attribute. The accuracy of the vertical position in metres at the 95% confidence level is defined by the ‘accuracyOfHeightAboveGroundLevel’ attribute.
Attribute Name: heightAboveGroundLevel (GML), height_above_ground_level (GeoPackage), N/A (Vector Tiles)
Multiplicity: [0..1]
Where known, indicates whether the real-world nature of the feature is man-made or natural.
Attribute Name: make (GML), Make (GeoPackage), N/A (Vector Tiles)
Multiplicity: [0..1]
This attribute states whether the feature is underground, obscured below normal cartographic level, at normal cartographic level or overhead.
Normal cartographic level is that perceived to be the normal surface level. Where an area feature overlies another (for example, bridges), they are at normal cartographic level and the features below them are recorded as obscured.
Indicates the physical level of a feature with reference to the normal cartographic surface level. Only four values are used:
Attribute Name: physicalLevel (GML), physical_level (GeoPackage), N/A (Vector Tiles)
Type: Integer
Multiplicity: [1]
This attribute indicates the nature of the object represented by the feature. This is normally used for TopographicLine, for example, a value of ‘obstructing’ indicates that the feature prevents pedestrian access, whereas a value of ‘edge/limit’ means that the feature represents a change of surface type and does not generally impede access. This attribute is also used to identify administrative boundary and inferred line features, and moveable area features (for example, moveable cranes).
Attribute Name: physicalPresence (GML), physical_presence (GeoPackage), N/A (Vector Tiles)
Multiplicity: [0..1]
A pair of easting and northing ordinates in metres, defining a horizontal location in the British National Grid spatial reference system.
Attribute Name: point
Type: GM_Point
Multiplicity: [1]
Descriptive group | Feature type | Descriptive term | Feature code |
---|---|---|---|
Descriptive group | Theme | Real-world examples | Description |
---|---|---|---|
Type:
Type:
Type:
Type:
Type:
Type:
Type:
Type:
Type: String; see
Type: String; see
Type:
Type:
Type:
Type:
Type:
Information about the change history of a feature that comprises the reason for the change and the date for this change. Each feature may have numerous change history records, and these are ordered chronologically. A .
Type:
Type:
Type:
Type:
Type:
Type:
Type:
Type:
Type: String; see
Type:
Type:
Type:
Type:
Type:
Type:
Type:
Type:
Variables | Value/s |
---|---|
Property/Description | Value/s |
---|---|
Name | Attributes | Colour | Visual |
---|---|---|---|
Name | Attributes | Colour | Visual |
---|---|---|---|
Compound symbol | Fill symbols | Shape |
---|---|---|
Compound symbol | Fill symbols | Shape |
---|---|---|
Symbol | Style and Geometry | Shape |
---|---|---|
Variables | Value/s |
---|---|
Variables | Value/s |
---|---|
Name | Attributes | Colour | Visual |
---|---|---|---|
Type:
Type:
Type:
Type:
Type:
Type:
Type:
Type:
Value | Description |
---|
Type:
Size
(25,25)
Suitable symbols
manmadeLandformFillSymbol
naturalLandformFillSymbol
Symbol coordinates
0,-21 0,-18 0,-15 0,-12 0,-9 0,-6 0,-3 0,0 0,3 0,6 0,9 0,12 0,15 0,18 0,21
Fill colour
none
Patterns
manmadeLandformPattern naturalLandformPattern
Size
(3,3)
Suitable symbols
foreshoreFillSymbol
multiVegetationFillSymbol
Fill colour
for foreshorePattern – CCFFF (RGB 204,255,255)
otherwise – CCFFCC (RGB 204,255,204)
Patterns
foreshorePattern
multiVegetationPattern
Size
(6,6)
Suitable symbols
orchardFillSymbol
Fill colour
CCFFCC (RGB 204,255,204)
Patterns
orchardPattern
Size
(50,50)
Suitable symbols
All natural vegetation and surface cover symbol types except for orchard.
Symbol coordinates
5,3 5,25 10,12 10,35 25,45 42,15 37,27 27,14 36,37 42,45 39,3 18,33
Fill colour
CCFFCC (RGB 204,255,204)
Patterns
roughGrassPattern heathPattern marshPattern scatteredBouldersPattern scatteredRocksPattern scatteredConiferousTreesPattern scatteredNonconiferousTreesPattern coppicePattern orchardPattern bouldersPattern rocksPattern screePattern scrubPattern coniferousTreesPattern nonconiferousTreesPattern coniferousTreesAndScatteredRocksPattern coniferousTreesAndScrubPattern heathAndScrubPattern heathAndScatteredRocksPattern nonconiferousTreesAndConiferousTreesPattern nonconiferousTreesAndCoppicePattern nonconiferousTreesAndScatteredRocksPattern nonconiferousTreesAndScrubPattern roughGrassAndBouldersPattern roughGrassAndConiferousTreesPattern roughGrassAndHeathPattern roughGrassAndMarshPattern roughGrassAndNonconiferousTreesPattern roughGrassAndRocksPattern roughGrassAndScatteredBouldersPattern roughGrassAndScatteredNonconiferousTreesPattern roughGrassAndScatteredRocksPattern roughGrassAndScrubPattern scatteredNonconiferousTreesAndScatteredConiferousTreesPattern scrubAndScatteredNonconiferousTreesPattern rocksRoughGrassAndBouldersPattern roughGrassNonconiferousTreesAndConiferousTreesPattern roughGrassNonconiferousTreesAndScrubPattern roughGrassScatteredRocksAndBouldersPattern roughGrassScatteredRocksAndHeathPattern roughGrassScatteredRocksAndScatteredBouldersPattern roughGrassScatteredNonconiferousTreesAndScrubPattern scrubConiferousTreesAndNonconiferousTreesPattern scrubNonconiferousTreesAndCoppicePattern scatteredConiferousTreesScatteredNonconiferousTreesAndScrubPattern
Unclassified
Symbol
N/A
10214
Unclassified
Text
N/A
10213
coniferousTreesFillSymbol
1: coniferousTreeFillSymbol
2: smallConiferousTreeFillSymbol
Fw5IonD25k80
nonconiferousTreesFillSymbol
1: nonconiferousTreeFillSymbol
2: smallNonconiferousTreeFillSymbol
XMdUZ2mkOAdR
scrubFillSymbol
1: bushFillSymbol
2: smallBushFillSymbol
qXHh1LCLW1GG
Size
(3,3)
Suitable symbols
foreshoreFillSymbol, multiVegetationFillSymbol, collectsAndSpreadsFillSymbol
Symbol coordinates
2,2
Fill colour
foreshorePattern – DCFFBE (RGB 204,255,255) collectsAndSpreadsPattern – DCFFBE (RGB 220,255,190) sandPattern - F7FF82 (RGB 247,255,125)
Patterns
foreshorePattern multiVegetationPattern collectsAndSpreadsPattern sandPattern
Size
(50,50)
Suitable symbols
All natural vegetation and surface cover symbol types except for orchard.
Symbol coordinates
5,3 5,25 10,12 10,35 25,45 42,15 37,27 27,14 36,37 42,45 39,3 18,33
Fill colour
ccffcc (RGB 204,255,204)
Patterns
roughGrassPattern heathPattern marshPattern scatteredBouldersPattern scatteredRocksPattern
scatteredConiferousTreesPattern scatteredNonconiferousTreesPattern
coppicePattern, orchardPattern bouldersPattern rocksPattern screePattern scrubPattern coniferousTreesPattern
nonconiferousTreesPattern reedsPattern saltmarshPattern shinglePattern
coniferousTreesAndScatteredRocksPattern coniferousTreesAndScrubPattern heathAndScrubPattern heathAndScatteredRocksPattern nonconiferousTreesAndConiferousTreesPattern nonconiferousTreesAndCoppicePattern nonconiferousTreesAndScatteredRocksPattern nonconiferousTreesAndScrubPattern roughGrassAndBouldersPattern roughGrassAndConiferousTreesPattern roughGrassAndHeathPattern roughGrassAndMarshPattern roughGrassAndNonconiferousTreesPattern roughGrassAndRocksPattern roughGrassAndScatteredBouldersPattern roughGrassAndScatteredNonconiferousTreesPattern roughGrassAndScatteredRocksPattern roughGrassAndScrubPattern
scatteredNonconiferousTreesAndScatteredConiferousTreesPattern
scrubAndScatteredNonconiferousTreesPattern rocksRoughGrassAndBouldersPattern
Buildings
Buildings
Factories, Houses, Public Convenience, Tank
Features representing buildings (not including glasshouses).
Buildings Or Structure
Buildings
Cartographic text intersecting buildings
Features representing the name, function, or use of a building or structure.
Built Environment
Land
Residential Land, Car Parks
Geographic areas and extents of man-made environments, terrain and communication links.
General Feature
Land
Cattle Grid, Conduit, Conveyor, Line of Posts, Lock Gate, Slipway, Sloping Masonry
General topographic features and minor detail.
General Surface
Land
Agricultural Land, Slag Heap, Slipway, Sloping Masonry, Spoil Heap, Tank
Features that denote surfaces that are man- made, though not specifically in man-made environments.
Glasshouse
Buildings
Greenhouses
Features representing glasshouses.
Height Control
Terrain and Height
Bench marks
Features with height information.
Historic Interest
Heritage and Antiquities
Site Of Heritage, such as a Battlefield
Features of heritage value, often depicted as text, indicating the site of a historic event or an actual physical historical structure, such as Hadrian’s Wall.
Inland Water
Water
Canals, Collects, Drains, Fords, Issues, Lakes, Leats, Reservoirs, Rivers,
Sinks, Spreads, Springs, Static Water, Streams, Watercourses, Waterfalls
Features representing, describing or limiting areas of water that are
not tidal.
Landform
Land
Caves, Mineral Workings, Slopes, Cliffs, Quarries
Features representing, describing or limiting areas of landform, for example, slopes or cliffs.
Natural Environment
Land
Marsh, Mud, Saltmarsh, Sand, Shingle, Scrub, Woodland
Features representing geographic areas and extents of natural environments and terrain.
Network or Polygon Closing Geometry
Land, and Road, Tracks and Paths
Road Junctions, Gardens
Features used to close network polygons at their termination.
Path
Roads, Tracks and Paths
Paths, Cycle Paths
Features representing and limiting the extent of pathways.
Political or Administrative
Administrative Boundary
County, District, Ward and Civil Parish boundaries and markers
Features representing political or electoral boundaries.
Rail
Roads, Tracks and Paths
Railway Land, Tracks and Signals
Features representing, describing or limiting the extents of railways.
Road or Track
Roads, Tracks and Paths
Road sections of varying surfaces, Roundabouts, Central Reservations
Features representing, describing or limiting the extents of roadways and tracks.
Roadside
Roads, Tracks and Paths
Verges, Pavements
Features representing, describing or limiting the extents of roadside detail.
Structure
Structures
Bridges, Chimneys, Groynes, Lighting Gantries, Lock Gates, Sluices, Telecommunications Masts, Weirs and Wind Turbines
Features representing, describing or limiting areas of water that are tidal.
Terrain and Height
Terrain and Height
Spot height marks
Features giving
information about the altitude at a location or changes of level of the ground surface.
Tidal Water
Water
Tidelines, including Mean High Water (MHW) / Mean Low Water (MLW), Mean High Water (Springs;
MHWS) / Mean Low Water (Springs; MLWS), Normal Tidal Limit (NTL) / Mean Spring Tide (MST)
Features representing, describing or limiting areas of water that are tidal
Unclassified
Land
Areas under temporary development
Features representing developing or undesignated attributes in the process of being captured.
Boolean
Value of ‘true’ or ‘false’.
Date
Specifies a day within the Gregorian calendar in the format YYYY-MM-DD.
Integer
Any positive or negative whole number or zero.
GM_MultiCurve
A set of Polyline geometries. See geometric data types for details.
GM_Point
A pair of easting and northing coordinates in metres, defining a horizontal location in the British National Grid spatial reference system. See geometric data types for details.
GM_Surface
A closed area defined by one outer boundary and zero or more inner boundaries (polygon). Each boundary is a closed ring of coordinate pairs, interpolated as for a polyline. See geometric data types for details.
GM_Curve
An ordered set of points that are connected with a straight line between each pair. See geometric data types for details.
Real
A floating point number.
Rectangle
A rectangle defined in the British National Grid.
String
An ordered set of characters.
TOID
OS MasterMap unique feature identifier.
-1 | Underground detail |
49 | Obscured detail below the normal cartographic level |
50 | Detail at the normal cartographic level |
51 | Overhead detail above normal cartographic level |
This defines the height above ground level of a feature (heightAboveGroundLevel attribute) and defines the accuracy of this, where known (accuracyOfHeightAboveGroundLevel attribute). This attribute is only present in the Topographic Line and the Topographic Point Feature Types.
Height of the feature above ground level, in metres. Forms part of the heightAboveGroundLevel complex attribute.
Attribute Name: heightAboveGroundLevel
Type: Real
Multiplicity: [1]
The accuracy of the vertical position in metres at the 95% confidence level. Forms part of the heightAboveGroundLevel complex attribute.
Attribute Name: accuracyOfHeightAboveGroundLevel
Type: String
Multiplicity: [1]
Building
Buildings Or Structure
Built Environment
General Feature
General Surface
Glasshouse
Height Control
Historic Interest
Inland Water
Landform
Natural Environment
Network Or Polygon Closing Geometry
Path
Political Or Administrative
Rail
Road Or Track
Roadside
Structure
Terrain And Height
Tidal Water
Unclassified
Provides the information to graphically display a text string in harmony with the underlying map detail and consists of anchorPosition, font, height and orientation attributes. This attribute is only present in the Cartographic Text Feature Type.
A number between 0 and 8 that specifies which part of the text is bound to the anchorPoint. Forms part of the feature’s complex attribute, textRendering.
Attribute Name: anchorPosition
Type: Integer
Multiplicity: [1]
A value of 0, 1, 2 or 3 that can be used as a basis for determining which font to use when displaying the text. For example, a user application could associate Verdana with 2 to display all text with a font of 2 in Verdana. Forms part of the feature’s complex attribute, textRendering.
Attribute Name: font
Type: Integer
Multiplicity: [1]
The height of CartographicText. The height is expressed as the distance on the ground covered by the text, in metres. Forms part of the feature’s complex attribute, textRendering.
Attribute Name: height
Type: Measure
Multiplicity: [1]
The orientation of text for cartographic placement. Given in tenths of a degree anticlockwise from due east (0–3599). Forms part of the feature’s complex attribute, textRendering.
Attribute Name: orientation
Type: Integer
Multiplicity: [1]
Features within OS MasterMap Topography Layer have a lifecycle which is matched, where possible, to that of the real-world object they represent. For example, a new building becomes a new object in the Ordnance Survey main database and is treated as one feature, even if it undergoes change, until the building is demolished. With this approach, Ordnance Survey is emulating real-world behaviour within a digital model. Not all change to the real-world object will be reflected in a change to the feature. For example, the addition of a new porch to a house would usually be considered too minor a change to capture.
Different applications of the data will require different views of feature lifecycles. For some users, any change to the geometry or classification of a feature means it is no longer the same feature for their application, whilst others need persistence of features – so a feature continues to exist through extensive modification. Understanding change is important to understanding OS MasterMap Topography Layer and deriving the optimum value from it.
Lifecycle rules adopt the approach of allowing features to persist through changes, so far as is reasonable. There is inevitably some subjectivity involved in judging that a real-world object has changed so much it can no longer be considered the same object, so specific rules exist to govern this.
Ordnance Survey provides persistent managed identifiers as Topographic Object Identifiers (TOIDs). A TOID is a unique identifier, consisting of the letters ‘osgb’ followed by either 13 or 16 digits between 0 and 9. The TOID is allocated sequentially when a feature is created by Ordnance Survey and is never reassigned to a different feature. One of the key principles of unique referencing is that the TOID will stay the same throughout the life of a feature. This gives the feature continuity within its lifecycle and makes managing change in a holding of the product easier.
The TOID is provided in the GML attribute ‘fid’ of the osgb:Feature element, as shown below:
<osgb:TopographicArea fid='osgb1000000324268289'>
The TOID is provided in the GeoPackage and vector tile attribute 'toid'.
TOIDs enable explicit, maintained references between features in different layers. Other OS MasterMap products reference Topography Layer polygon features within which they are located, allowing the user to navigate between OS MasterMap products using the TOID.
The allocated TOID should never be shortened or amended as this will result in it not being compatible with other OS MasterMap products.
Although the nature of a feature might remain essentially the same throughout its life, it is likely to undergo change to its geometry or attributes. Each feature has a version number which is incremented each time there is change of any kind to the feature via one of its attributes. The change can be due either to real- world change or to processes not connected with a real-world change, such as error correction, geometric cleaning, and structuring of the data.
The previous version is referred to as the superseded version, and the new version as the superseding version. In a small minority of cases, a new version of a feature can be created without any apparent change to the product. This is due to change to internal database attributes used in the maintenance process but not included in product data.
The date on which the new version is created is recorded in the feature version date attribute. The date is important for tracking and identifying when change has taken place. Using the TOID, the version number and the version date, it is possible to track a feature’s changes over time. The date the version changed for Ordnance Survey will be different from the date on which the feature is loaded into the user’s file or database holding. Many translators provide an additional column to record the load date. It is important for the user to identify these dates in their holdings and to understand the difference between them if they want to be able to track changes.
One of the key differences between OS MasterMap features and other products is that, with the correct data storage model, a data holding can be rolled back and forward to a given point in time. It must be emphasised that this is the user’s responsibility, since only the current version is available in the product; none of the previous versions are included.
The following sub-sections set out the rules that define the lifecycles of features in OS MasterMap Topography Layer. By understanding how change is defined and recorded within the product, users can start to identify what kind of change has a bearing on their applications and develop their own management regimes.
Agricultural Land
Aqueduct
Archway
Bench Mark
Bottom Of Cliff
Bottom Of Slope
Boulders
Boulders (Scattered)
Boundary Half Mereing
Boundary Post Or Stone
Bridge
Buffer
Canal
Canal Feeder
Capstan
Cattle Grid
Cave
Chimney
Collects
Compound
Conduit
Coniferous Trees
Coniferous Trees (Scattered)
Conveyor
Coppice Or Osiers
County
Course Of Heritage
Crane
Cross
Culvert
Direction Of Flow
Distance Marker
District
Disused Feature
Division
Drain
Electoral
Electricity Sub Station
Emergency Telephone
Flagstaff
Footbridge
Ford
Foreshore
Fountain
Gantry
Gas Governor
Groyne
Guide Post
Heath
Inferred Property Closing Link
Issues
Landfill
Landfill (Inactive)
Letter Box
Level Crossing
Lighting Gantry
Line Of Mooring Posts
Line Of Posts
Lock
Lock Gate
Marth
Marsh Reeds Or Saltmarsh
Mast
Mean High Water (Springs)
Mean Low Water (Springs)
Mill Leat
Mine Leat
Mineral Workings
Mineral Working (Inactive)
Mooring Post
Mud
Multi Surface
Narrow Gauge
Nonconiferous Trees
Nonconiferous Trees (Scattered)
Normal Tidal Limit
Orchard
Outline
Overhead Construction
Parish
Parliamentary
Pole
Polygon Closing Link
Positioned Boulder
Positioned Coniferous Tree
Positioned Nonconiferous Tree
Post
Public
Public Convenience
Public Telephone
Pylon
Rail Signal Gantry
Reed
Reservoir
Ridge Or Rock Line
Road Name Or Classification
Road Related Flow
Rock
Rock (Scattered)
Rough Grassland
Saltmarsh
Sand
Scree
Scrub
Shingle
Signal
Sinks
Site Of Heritage
Slag Heap
Slag Heap (Inactive)
Slipway
Slope
Sloping Masonry
Sluice
Spoil Heap
Spoil Heap (Inactive)
Spot Height
Spreads
Spring
Standard Gauge Track
Static Water
Step
Structure
Swimming Pool
Switch
Tank
Telecommunications Mast
Top Of Cliff
Top Of Slope
Track
Traffic Calming
Triangulation Point Or Pillar
Tunnel Edge
Unmade Path Alignment
Upper Level Of Communication
Watercourse
Waterfall
Waterfall (Vertical)
Weir
Well
Wind Turbine
The lifecycles of point features are simpler than those of lines or polygons since they cannot change in size or be split into multiple features.
When a new real-world object comes into being, a new point feature is created to represent it. If, however, the object is a replacement for a previous real-world object in the same position, the original feature is retained. An example would be if an existing post box was replaced by another post box in the same location.
When a real-world object is no longer present in the real world, the point feature is removed from Ordnance Survey’s holding. Ordnance Survey keeps a record to indicate that the feature with this TOID used to exist and notifies the user at the next date of COU supply.
By the nature of the real-world objects represented as point features in OS MasterMap Topography Layer data, it is unlikely that one will be modified without changing its identity. Therefore, any modification to a point feature as a result of real-world change will result in the deletion of the original feature and creation of a new feature, unless there is a clear reason to identify the resultant real-world object with the original. This applies to both geometric change and change of descriptive group or descriptive term.
When a point feature is found to be incorrectly attributed due to an error or is moved due to the correction of a positional accuracy error, the original feature is retained and appropriately modified.
This section has explained in some detail the lifecycles of features so that users can understand how the data is managed by Ordnance Survey.
defaultLine
stroke-width – 0.07
333333
defaultDashedLine
stroke-width – 0.1
stroke-dasharray – 0.5, 0.5
333333
buildingLine
stroke-width – 0.07
000000
buildingOverheadLine
stroke-width – 0.1
stroke-dasharray – 0.5, 0.5
000000
waterBoldLine
stroke-width – 0.4
00CCFF
waterLine
stroke-width – 0.07
0099FF
defaultUndergroundLine
stroke-width – 0.2
stroke-dasharray – 3.0, 1.0
333333
structureOverheadLine
stroke-width – 0.2
stroke-dasharray – 2.0, 1.0
CC9966
landformBoldLine
stroke-width – 0.3
stroke-dasharray – 0.8, 0.8
D06800
landformLine
stroke-width – 0.1
stroke-dasharray – 0.8, 0.8
E07000
narrowGaugeRailwayAlignmentLine
stroke-width – 0.3
333333
standardGaugeRailLine
stroke-width – 0.15
333333
parishLine
stroke-width – 0.4
stroke-dasharray – 0.4, 0.8
FF00FF
electoralLine
stroke-width – 0.2
stroke-dasharray – 1.5, 0.5
FF00FF
countyLine
stroke-width – 0.4
stroke-dasharray – 2.0, 1.0
FF00FF
parliamentaryLine
stroke-width – 0.4
stroke-dasharray – 1.8, 0.5
FF00FF
districtLine
stroke-width – 0.3
stroke-dasharray – 1.5, 0.8
FF00FF
closingLine
stroke-width – 0.05
stroke-dasharray – 0.5, 0.5
FF0000
bushFillSymbol: translate(-0.8 1)
smallBushFillSymbol: translate(1.2 –1.2)
The combined result, scrubFillSymbol, is drawn as:
roughGrassFillSymbol: translate(-1 -1)
scrubFillSymbol: translate(1 1)
The combined result, roughGrassAndScrubFillSymbol, is drawn as:
bouldersFillSymbol
1: boulderFillSymbol
2: smallBoulderFillSymbol
rocksFillSymbol
1: rockFillSymbol
2: smallRockFillSymbol
coniferousTreesAndScrubFillSymbol
1: coniferousTreesFillSymbol 2: scrubFillSymbol
heathAndScrubFillSymbol
1: heathFillSymbol 2: scrubFillSymbol
heathAndScatteredRocksFillSymbol
1: heathFillSymbol 2: smallRockFillSymbol
nonconiferousTreesAndConiferousTreesFillSymbol
1: nonconiferousTreesFillSymbol 2: coniferousTreesFillSymbol
nonconiferousTreesAndCoppiceFillSymbol
1: nonconiferousTreesFillSymbol 2: coppiceFillSymbol
nonconiferousTreesAndScrubFillSymbol
1: nonconiferousTreesFillSymbol 2: scrubFillSymbol
nonconiferousTreesAndScatteredRocksFillSymbol
1: nonconiferousTreesFillSymbol 2: smallRockFillSymbol
coniferousTreesAndScatteredRocksFillSymbol
1: coniferousTreesFillSymbol 2: smallRockFillSymbol
roughGrassAndBouldersFillSymbol
1: roughGrassFillSymbol 2: bouldersFillSymbol
roughGrassAndConiferousTreesFillSymbol
1: roughGrassFillSymbol 2: coniferousTreesFillSymbol
roughGrassAndHeathFillSymbol
1: roughGrassFillSymbol 2: heathFillSymbol
roughGrassAndMarshFillSymbol
1: roughGrassFillSymbol 2: marshFillSymbol
roughGrassAndNonconiferousTreesFillSymbol
1: roughGrassFillSymbol 2: nonconiferousTreesFillSymbol
roughGrassAndRocksFillSymbol
1: roughGrassFillSymbol 2: rocksFillSymbol
roughGrassAndScatteredBouldersFillSymbol
1: roughGrassFillSymbol 2: smallBouldersFillSymbol
roughGrassAndScatteredNonconiferousTreesFillSymbol
1: roughGrassFillSymbol 2: smallNonconiferousTreeFillSymbol
roughGrassAndScatteredRocksFillSymbol
1: roughGrassFillSymbol 2: smallRockFillSymbol
roughGrassAndScrubFillSymbol
1: roughGrassFillSymbol 2: scrubFillSymbol
scatteredNonconiferousTreesAndScatteredConiferousTreesFillSymbol
1: smallNonconiferousTreeFillSymbol 2: smallConiferousTreeFillSymbol
scrubAndScatteredNonconiferousTreesFillSymbol
1: scrubFillSymbol 2: smallNonconiferousTreeFillSymbol
rocksRoughGrassAndBouldersFillSymbol
1: rocksFillSymbol
2: roughGrassFillSymbol
3: bouldersFillSymbol
roughGrassNonconiferousTreesAndConiferousT reesFillSymbol
1: roughGrassFillSymbol
2: nonconiferousTreesFillSymbol
3: coniferousTreesFillSymbol
roughGrassNonconiferousTreesAndScrubFillSym bol
1: roughGrassFillSymbol
2: nonconiferousTreesFillSymbol
3: scrubFillSymbol
scrubNonconiferousTreesAndCoppiceFillSymbol
1: scrubFillSymbol
2: nonconiferousTreesFillSymbol
3: coppiceFillSymbol
scrubConiferousTreesAndNonconiferousTreesFi llSymbol
1: scrubFillSymbol
2: coniferousTreesFillSymbol
3: nonconiferousTreesFillSymbol
roughGrassScatteredRocksAndBouldersFillSymbol
1: roughGrassFillSymbol
2: smallRockFillSymbol
3: bouldersFillSymbol
roughGrassScatteredRocksAndHeathFillSymbol
1: roughGrassFillSymbol
2: smallRockFillSymbol
3: heathFillSymbol
roughGrassScatteredRocksAndScatteredBouldersFill Symbol
1: roughGrassFillSymbol
2: smallRockFillSymbol
3: smallBoulderFillSymbol
roughGrassScatteredNonconiferousTreesAndScrub FillSymbol
1: roughGrassFillSymbol
2: smallNonconiferousTreeFillSymbol
3: scrubFillSymbol
scatteredConiferousTreesScatteredNonconiferousT reesAndScrubFillSymbol
1: smallConiferousTreeFillSymbol
2: smallNonconiferousTreeFillSymbol
3: scrubFillSymbol
AAD48C (170,212,140)
agriculturalLandFill
6CC0D8 (108,193,217)
constructedWaterFill
F5F0E1 (245,240,225)
mudFill
F7FF82 (247,255,125)
sandFill
B7B789 (183,184,138)
slopingMasonryFill
D1DACD (209, 218, 205)
shingleFill
caveSymbol
Style:
stroke:#000000;fill:#D9D9D9;stroke-width:0.150
Geometry:
<circle id="circleGeometry" r="0.375" cx="0" cy="0"/> "#circleGeometry" x="0" y="0"/>
crossSymbol
Style:
stroke:#000000; fill:none; stroke-width:0.087
Geometry:
<polyline points=‘0.000,-0.775 0.000,0.775’/>
<polyline points=‘-0.385,0.385 0.385,0.385’/>
emergencyTele phoneSymbol
emergencyTelephoneSymbol Style:
stroke:#FF0000;fill:#FF0000;stroke-width:0.087
Geometry:
circleGeometry (see Shared symbol geometry)
postboxSymbol
Style:
stroke:#000000;fill:#FF0000;stroke-width:0.087 Geometry:
circleGeometry (see Shared symbol geometry)
signalSymbol
Style:
stroke:#000000;fill:#FFAD00;stroke-width:0.087 Geometry:
circleGeometry (see Shared symbol geometry)
collectsAndSpreadsFillSymbol
stroke:#0099ff;fill:#0099ff;stroke-width:0.087 circleFillGeometry
saltmarshFillSymbol
fill:none;stroke-width:0.087
<g style='stroke:#0099FF'><polyline points='4.258,0.000 0.452,0.000' /><polyline points='-4.250,0.000 -0.444,0.000' /><polyline points='-1.318,-0.517 1.317,-0.517' /></g><g style='stroke:#0099FF;'><polyline points='-0.444,0.000 -0.534,1.0' /><polyline points='0.452,0.000 0.541,1.0' /><polyline points='-0.001,0.013 -0.001,1.177' /><polyline points='0.880,0.000 1.118,0.675' /><polyline points='-0.873,0.000 -1.110,0.675' /><polyline points='-1.318,0.000 -1.440,0.269' /><polyline points='1.326,0.000 1.447,0.269' /></g>
sandFillSymbol
stroke:#666666;fill:#666666;stroke-width:0.087 circleFillGeometry
reedsFillSymbol
stroke:#0099FF;fill:none;stroke-width:0.087
<polyline points='-1.487,-0.75 -1.601,-0.208' /><polyline points='-0.996,-0.613 -1.121,0.405' /><polyline points='-0.499,-0.545 -0.55,0.695' /><polyline points='0,-0.536 0,0.732' /><polyline points='0.499,-0.545 0.55,0.695' /><polyline points='0.996,-0.613 1.121,0.405' /><polyline points='1.487,-0.75 1.601,-0.208' />
shingleFillSymbol
stroke:#666666;fill:none;stroke-width:0.087
<polyline points='0.215,0.103 0.081,0.541 0.317,0.811 0.756,0.98 0.992,0.743 1.161,0.44 0.992,0.305 0.823,0.068 0.655,-0.066 '/><polyline points='0.123,-0.953 -0.317,-1.087 -0.587,-0.849 -0.754,-0.409 -0.517,-0.174 -0.212,-0.006 -0.077,-0.175 0.159,-0.345 0.293,-0.515 '/><polyline points='-1.044,0.734 -0.871,1.058 -0.583,1.076 -0.239,0.922 -0.241,0.653 -0.317,0.386 -0.491,0.406 -0.72,0.369 -0.893,0.388 '
seaDefenceLine
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postsLine
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Change-Only Update (COU) is only available for GML format orders. COU is unavailable in GeoPackage or vector tile formats.
COU is data that is provided to bring a user’s data holdings up to date with the most recent data available from Ordnance Survey. COU contains, for a user’s defined area, only the features that are new or have changed (known as Inserts and Updates, respectively), as well as departed features (i.e. those features that have moved or have been deleted from the user’s data extent; known as Deletes). Any feature that is new or changed since the COU date the user provides will be supplied in its latest version and departed features will indicate which features have been moved or deleted since that date.
COU will not provide intermediate versions of features that have existed between the previous order and the most recent version. Conversely, COU may supply departed information for features that the user has never had, as they have appeared and subsequently disappeared between order dates.
COU data is supplied in GML 2.1.2 format. Inclusion of features in the COU file is triggered by a new version of a feature appearing in the database with a version date between the previous and new order dates. In the data, these new and modified features (i.e. Inserts and Updates) are represented in the same way they would for a Full Supply. Departed Feature (i.e. Deletes) is a specific feature type only present in COU supply; it represents features to be removed from a user’s holding. The departed feature’s records contain the TOID of the deleted feature, its bounding rectangle, its theme or themes, and the date and reason for its departure.
Features that indicate that a feature in a previous supply may no longer be relevant, for example, it may have been deleted or moved. This feature type is used in COU data supply only.
The unique topographic reference number. It consists of the letters ‘osgb’ followed by thirteen or sixteen digits. The TOID must always be retained/stored in its entirety as any changes, including removal of digits, will make the TOID unusable with other OS MasterMap products.
Type: String
Multiplicity: [1]
The minimum enclosing rectangle that encompasses a geometry. For departedFeatures, this encompasses all geometries that a feature has had in its lifecycle.
Type: Rectangle
Multiplicity: [1]
A theme that the feature belongs to.
Type: String; see ThemeType
Multiplicity: [1..*]
This is set to ‘Deleted’ or ‘Vacated’ to indicate whether a feature has physically been deleted from the database or is no longer relevant due to change in COU supply.
Type: String
Multiplicity: [1]
The date the feature was deleted from the Ordnance Survey maintenance database.
Type: Date
Multiplicity: [0..1]
COU requires that information be provided for features that were present in a spatial query but no longer meet the query criteria. Such features may have changed theme so that they:
Are no longer in any of the themes being requested.
Have had their geometry modified between queries so that they no longer meet the spatial criteria.
Have been deleted.
These features are represented using the DepartedFeature Feature Type explained above. These are encoded the same way as other features.
For example:
A rectangle is a pair of points that are used to define a rectangular area that is aligned to the National Grid. One point defines the minimum easting and northing of the rectangle, the other defines the maximum easting and northing.
Example
Example class model:
All the information to update a user’s holding is provided in the COU file. How this is processed by the user’s software is obviously critical to ensuring that these changes are correctly applied. The basic principles that need to be followed to help ensure consistency are:
Ensure that the Initial Supply or latest Full Supply or COU has been correctly loaded. This can be checked with the feature validation dataset (FVDS), which gives a full list of the TOIDs that should be in a user’s current holding at time of Full Supply.
Ensure that the COU to be applied covers the period from the date of last supply (‘Extraction date’) through to the update date required.
Apply the COU to the existing holding. How this is applied will be dependent upon the user’s system.
Check the holding using the FVDS at appropriate intervals to ensure currency and consistency of data holdings.
Below are three real-world examples of how the rural land cover specification refinement has affected the data within OSMM Topography Layer. The examples showcase three areas in southern Scotland where the specification refinement has broken up one land polygon within the Topographic Area Feature Type into smaller, separate polygons.
OSMM Topography Layer (July 2022): osgb1000000316775097
OSMM Topography Layer (August 2022): osgb5000005297485451, osgb5000005297485455, osgb5000005297485456
Source imagery of example area one for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – July 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
OSMM Topography Layer (July 2022): osgb1000000318639911
OSMM Topography Layer (August 2022): osgb1000000318639911, osgb5000005298080383, osgb5000005298080465
Source imagery of example area two for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
OSMM Topography Layer (July 2022): osgb1000000319079420
OSMM Topography Layer (August 2022): osgb1000000319079420, osgb5000005298106224
Source imagery of example area three for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
Below are three real-world examples of how the rural land cover specification refinement has affected the data within OSMM Topography Layer. The examples showcase three areas in southern Scotland where the specification refinement has broken up one land polygon within the Topographic Area Feature Type into smaller, separate polygons.
OSMM Topography Layer (July 2022): osgb1000000316775097
OSMM Topography Layer (August 2022): osgb5000005297485451, osgb5000005297485455, osgb5000005297485456
Source imagery of example area one for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – July 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
OSMM Topography Layer (July 2022): osgb1000000318639911
OSMM Topography Layer (August 2022): osgb1000000318639911, osgb5000005298080383, osgb5000005298080465
Source imagery of example area two for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
OSMM Topography Layer (July 2022): osgb1000000319079420
OSMM Topography Layer (August 2022): osgb1000000319079420, osgb5000005298106224
Source imagery of example area three for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
Below are three real-world examples of how the rural land cover specification refinement has affected the data within OSMM Topography Layer. The examples showcase three areas in southern Scotland where the specification refinement has broken up one land polygon within the Topographic Area Feature Type into smaller, separate polygons.
OSMM Topography Layer (July 2022): osgb1000000316775097
OSMM Topography Layer (August 2022): osgb5000005297485451, osgb5000005297485455, osgb5000005297485456
Source imagery of example area one for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – July 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
OSMM Topography Layer (July 2022): osgb1000000318639911
OSMM Topography Layer (August 2022): osgb1000000318639911, osgb5000005298080383, osgb5000005298080465
Source imagery of example area two for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
OSMM Topography Layer (July 2022): osgb1000000319079420
OSMM Topography Layer (August 2022): osgb1000000319079420, osgb5000005298106224
Source imagery of example area three for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
Below are three real-world examples of how the rural land cover specification refinement has affected the data within OSMM Topography Layer. The examples showcase three areas in southern Scotland where the specification refinement has broken up one land polygon within the Topographic Area Feature Type into smaller, separate polygons.
OSMM Topography Layer (July 2022): osgb1000000316775097
OSMM Topography Layer (August 2022): osgb5000005297485451, osgb5000005297485455, osgb5000005297485456
Source imagery of example area one for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – July 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
OSMM Topography Layer (July 2022): osgb1000000318639911
OSMM Topography Layer (August 2022): osgb1000000318639911, osgb5000005298080383, osgb5000005298080465
Source imagery of example area two for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
OSMM Topography Layer (July 2022): osgb1000000319079420
OSMM Topography Layer (August 2022): osgb1000000319079420, osgb5000005298106224
Source imagery of example area three for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
Below are three real-world examples of how the rural land cover specification refinement has affected the data within OSMM Topography Layer. The examples showcase three areas in southern Scotland where the specification refinement has broken up one land polygon within the Topographic Area Feature Type into smaller, separate polygons.
OSMM Topography Layer (July 2022): osgb1000000316775097
OSMM Topography Layer (August 2022): osgb5000005297485451, osgb5000005297485455, osgb5000005297485456
Source imagery of example area one for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – July 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
OSMM Topography Layer (July 2022): osgb1000000318639911
OSMM Topography Layer (August 2022): osgb1000000318639911, osgb5000005298080383, osgb5000005298080465
Source imagery of example area two for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
OSMM Topography Layer (July 2022): osgb1000000319079420
OSMM Topography Layer (August 2022): osgb1000000319079420, osgb5000005298106224
Source imagery of example area three for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
Below are three real-world examples of how the rural land cover specification refinement has affected the data within OSMM Topography Layer. The examples showcase three areas in southern Scotland where the specification refinement has broken up one land polygon within the Topographic Area Feature Type into smaller, separate polygons.
OSMM Topography Layer (July 2022): osgb1000000316775097
OSMM Topography Layer (August 2022): osgb5000005297485451, osgb5000005297485455, osgb5000005297485456
Source imagery of example area one for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – July 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
OSMM Topography Layer (July 2022): osgb1000000318639911
OSMM Topography Layer (August 2022): osgb1000000318639911, osgb5000005298080383, osgb5000005298080465
Source imagery of example area two for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
OSMM Topography Layer (July 2022): osgb1000000319079420
OSMM Topography Layer (August 2022): osgb1000000319079420, osgb5000005298106224
Source imagery of example area three for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
Below are three real-world examples of how the rural land cover specification refinement has affected the data within OSMM Topography Layer. The examples showcase three areas in southern Scotland where the specification refinement has broken up one land polygon within the Topographic Area Feature Type into smaller, separate polygons.
OSMM Topography Layer (July 2022): osgb1000000316775097
OSMM Topography Layer (August 2022): osgb5000005297485451, osgb5000005297485455, osgb5000005297485456
Source imagery of example area one for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – July 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
OSMM Topography Layer (July 2022): osgb1000000318639911
OSMM Topography Layer (August 2022): osgb1000000318639911, osgb5000005298080383, osgb5000005298080465
Source imagery of example area two for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
OSMM Topography Layer (July 2022): osgb1000000319079420
OSMM Topography Layer (August 2022): osgb1000000319079420, osgb5000005298106224
Source imagery of example area three for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
Below are three real-world examples of how the rural land cover specification refinement has affected the data within OSMM Topography Layer. The examples showcase three areas in southern Scotland where the specification refinement has broken up one land polygon within the Topographic Area Feature Type into smaller, separate polygons.
OSMM Topography Layer (July 2022): osgb1000000316775097
OSMM Topography Layer (August 2022): osgb5000005297485451, osgb5000005297485455, osgb5000005297485456
Source imagery of example area one for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – July 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
OSMM Topography Layer (July 2022): osgb1000000318639911
OSMM Topography Layer (August 2022): osgb1000000318639911, osgb5000005298080383, osgb5000005298080465
Source imagery of example area two for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
OSMM Topography Layer (July 2022): osgb1000000319079420
OSMM Topography Layer (August 2022): osgb1000000319079420, osgb5000005298106224
Source imagery of example area three for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
Below are three real-world examples of how the rural land cover specification refinement has affected the data within OSMM Topography Layer. The examples showcase three areas in southern Scotland where the specification refinement has broken up one land polygon within the Topographic Area Feature Type into smaller, separate polygons.
OSMM Topography Layer (July 2022): osgb1000000316775097
OSMM Topography Layer (August 2022): osgb5000005297485451, osgb5000005297485455, osgb5000005297485456
Source imagery of example area one for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – July 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
OSMM Topography Layer (July 2022): osgb1000000318639911
OSMM Topography Layer (August 2022): osgb1000000318639911, osgb5000005298080383, osgb5000005298080465
Source imagery of example area two for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
OSMM Topography Layer (July 2022): osgb1000000319079420
OSMM Topography Layer (August 2022): osgb1000000319079420, osgb5000005298106224
Source imagery of example area three for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
Below are three real-world examples of how the rural land cover specification refinement has affected the data within OSMM Topography Layer. The examples showcase three areas in southern Scotland where the specification refinement has broken up one land polygon within the Topographic Area Feature Type into smaller, separate polygons.
OSMM Topography Layer (July 2022): osgb1000000316775097
OSMM Topography Layer (August 2022): osgb5000005297485451, osgb5000005297485455, osgb5000005297485456
Source imagery of example area one for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – July 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
OSMM Topography Layer (July 2022): osgb1000000318639911
OSMM Topography Layer (August 2022): osgb1000000318639911, osgb5000005298080383, osgb5000005298080465
Source imagery of example area two for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
OSMM Topography Layer (July 2022): osgb1000000319079420
OSMM Topography Layer (August 2022): osgb1000000319079420, osgb5000005298106224
Source imagery of example area three for comparative purposes:
Data before the rural land cover specification refinement update (OSMM Topography Layer – August 2022):
Data after the rural land cover specification refinement update (OSMM Topography Layer – October 2022):
Line features in OS MasterMap Topography Layer are not as persistent in the same way as polygon and point features. This is because line features are maintained by what are called topological structuring rules. If a line feature is intersected by another line, it is broken at the intersection. This means that a single linear real-world object is often represented by several line features – no real-world object should ever be made up with a partial line feature. There is no concept in OS MasterMap Topography Layer of a line feature that is made up of multiple line geometry elements.
An illustration of this rule is shown in the diagram below. A fence cuts a field into two real-world objects. A new fence is built at right angles to the original to further divide one half of the field. Although the old fence has not changed at all, it will be split into two separate line features.
As there is no recorded relationship between OS MasterMap Topography Layer line features and discrete real-world objects, a change to a line feature may result in the deletion or significant modification of that feature and the creation of new line features. This change is not necessarily caused by a real-world change to the linear object. In the example above, the original line feature is retained as one of the resultant line features; the other line feature is new. The user cannot predict which of the resultant line features will bear the original TOID. The major exception to this is that when the reason for change is a correction of error rather than real-world change, then features are retained whenever possible.
The more rapidly changing lifecycle means that associating user data with OS MasterMap Topography Layer line features by TOID references needs to be considered very carefully, as there will be greater overheads in terms of managing change. In most cases, it will be more practical to associate with points and polygons, rather than lines.
Inferred links are a particular type of line feature that do not actually exist in the real world. An inferred link is a line that Ordnance Survey has introduced into the data to make some types of polygons into more manageable units. There are two main uses:
Network closing links are frequently found where road polygons meet at junctions. If the roads were not split in this way, the Road theme would contain numerous very large polygons that would not be particularly useful in terms of being able to derive data or attach meaningful attribution to them. Roads with comparatively few junctions, such as motorways, are also split where another feature crosses them, such as a road bridge or footbridge.
Polygon closing links are used to make more manageable, or logical, polygons. The types of link are shown in the figure below. One example would be the creation of a link to separate an open-plan garden around a pair of semi-detached houses into two distinct entities, reflecting that there are two properties there in the real world. It must be stressed that these polygon closing links do not constitute the legal boundary of any property any more than a physical line feature does. These links are clearly identified in the ‘descriptive group’ attribution and could be filtered out in most GIS if a user wishes not to display them.
When a new linear real-world object comes into being, a new line feature is created to represent it.
When a real-world object is no longer present in the real world, the corresponding line feature is deleted from the Ordnance Survey main holding. A record is kept in the database to indicate that a feature with this TOID used to exist. Users with local holdings of OS MasterMap Topography Layer data are informed of the deletion in their next COU.
As noted above, a line feature may be modified due to changes to the real-world object, or due to changes in adjacent real-world objects. The original feature may be retained if a portion of its geometry remains and one or more new features may be created to reflect the change. If the classification attributes of a line change, then it will usually be retained, and the version number incremented. Occasionally, a line feature may be replaced with a seemingly identical line feature that is considered a new feature. For example, where a line is created to represent a newly erected fence placed along the alignment of an existing line boundary between a garden and the pavement.
When a line feature is changed solely to correct a surveying or cartographic error, the feature is retained, unless the resulting topological changes with adjacent features make this inappropriate.
A principle of OS MasterMap Topography Layer is that data is seamless, which means there are no fixed units of data supply. The nominal boundary of each packet of OS MasterMap Topography Layer data is defined by the user’s data selection polygon and by the data chunking method applied to break the supply into manageable units (if used).
With respect to the nominal boundary, data is supplied unclipped. This means that all features with geometry that overlaps the nominal boundary are supplied in their entirety.
There are occasions when a data update will temporarily leave a feature in an inconsistent state. This occurs when neighbouring data is updated, and the edits are applied to the seamless database at different times. According to the type of feature, the following results may be realised:
A break in a polygon boundary on the edge of an update area will cause neighbouring features to take on identical geometric properties and the broken line work to be removed from all polygon structuring. Once the update is completed, the polygons will resume their respective boundaries.
Where a polygon boundary is broken and there is no neighbouring polygon, the feature will be temporarily removed from supply. A query on this area between updates will not return the broken feature. A change- only query will return a departed feature (i.e. a Delete) to indicate that this feature has been removed from the supply. Once the complete edit has been applied to the database, the feature will be supplied with its original identity and history.
A polyline that crosses an updated area boundary may occasionally be broken by a partial update. Where this occurs, the line is flagged as broken and the component parts will be output separately in a multiline geometry.
Some polygons have inner boundaries that have a common point with each other or with the outer boundary. In this case, each loop formed where the boundary returns to the common point is treated as a separate boundary.
This polygon has an outer boundary (ABCDEA) and two inner boundaries (AHGFA and GKJIG).
All feature types are presented in British National Grid (BNG) as one of the four data types specified below:
A point is used to specify a single x,y location by a coordinate pair in a given spatial reference system.
A point defined in the BNG reference system has easting and northing ordinates in units of metres, where the easting is in the range of 0 to 700000 and the northing is in the range of 0 to 1300000. Coordinates are output to millimetre precision and are output in the data as float64 real types.
A polyline is an ordered set of points that are interpolated linearly. A polyline may not intersect itself or contain repeated points.
Example class model
A multiline is a collection of polyline geometries. There are no specific semantics or rules applied to the collection.
Example class model
A polygon is a single closed region on the spatial reference system projection plane, defined by a set of geometric rings that represent the boundaries. A polygon has one outer boundary and zero or more inner boundaries (holes in the polygon). The inner boundaries must not cross each other or contain other inner boundaries. Coordinates in outer boundaries are oriented in an anticlockwise direction; coordinates in inner boundaries are oriented in a clockwise direction.
Example class model
The flowchart below shows the process followed whenever a real-world object represented as an OS MasterMap Topography Layer polygon feature appears, changes, or is removed from the physical environment (i.e. referred to as Inserts, Updates and Deletes). The rules are described in more detail in the following sub-sections, particularly the guidelines used to answer the question in the centre of the flowchart (i.e. 'Is it still the same real-world object?').
When a new real-world object with an area (for example, a building or pond) comes into being, a new polygon feature is created in the data, with a new TOID and version number. Users with local holdings of OS MasterMap Topography Layer data will be informed of new features in their holding via Change-Only Update (COU).
When an object represented as a polygon feature no longer exists in the real world, the polygon feature is deleted from the database. A record is kept in the database to indicate that a feature with this TOID used to exist and when it was deleted. Users with local holdings of OS MasterMap data are informed of the deletion in their next COU.
When an object represented as a polygon feature changes but is considered to be still the same real-world object, the corresponding modified feature is retained in the database. The version number is incremented and the date on which the new version became current is stored.
If, however, the real-world object has undergone change to such a degree that it is not considered to be the same object as before, the polygon feature representing it is deleted and one or more new features created.
When a real-world polygon object expands or contracts, due to alteration to its bounding lines, it is considered to be the same real-world object, and as such retains its TOID. For example, the polygon feature representing the back garden of a property is retained, even if it is greatly reduced in size due to extension work done to the house. This is because its identity and association to a property remains unchanged despite extensive changes to its geometry.
If it is not clear whether the real-world object after modification is the same object or a new one, the following considerations are used as a guideline:
Is there topographic information to suggest the function of the resultant real-world object is the same as that of the original?
Is the resultant real-world object more than half the size and less than twice the size of the original?
Does the majority of the extent of the resultant real-world object lie within the bounds of the original?
Is the resultant real-world object the obvious logical successor to the original?
If the continuation of the feature cannot be justified on one or more of these grounds, the feature is deleted and replaced with a new feature.
A private house is extended. The building and garden features are retained.
A field changes shape and reduces in size due to the realignment of one of its boundary fences alongside a road. The field feature and the adjacent road features are retained.
When a real-world polygon object is split into two or more separate real-world objects, one of the features may be clearly recognisable as the original real-world object. If this is the case, then the feature is retained.
If it is not clear whether one of the resultant features represents the same real-world object as the original feature, then the following considerations are used as a guideline:
Is the function of one of the resultant real-world objects the same as the original?
Is one of the resultant real-world objects the obvious logical successor to the original?
Does one of the resultant real-world objects occupy more than half the area of the original?
If the continuation of the feature cannot be justified on one or more of these grounds, the original feature is deleted and replaced with new features.
A new housing development is completed within an agricultural field. Part of the field remains and continues to be used for agriculture. The feature representing the remainder of the field is recognisable as the original with the same function, therefore it is retained. New polygon features are created to represent the new housing development.
An agricultural field is subdivided into three approximately equal parts that continue to be in similar usage. Using the guidelines above, none of the fields can be considered the obvious successor to the original field: all have an area less than half of the original; therefore, the original feature is deleted and three new features are created.
A house is divided equally in two by an externally surveyable division. The original feature is deleted and new features are created. This is because neither of the resultant houses is the obvious successor to the original.
A large agricultural building is split into two by the addition of an externally surveyable division enclosing approximately 25% of the original area. The original feature is retained to represent the larger part, and a new feature is created to represent the smaller part.
Most of the large garden of a residential property is sold off for development. The garden feature is retained to represent the much-reduced garden.
When two or more real-world polygon objects are merged by the removal of physical boundaries, it may be that one of the original real-world objects is clearly recognisable as subsuming the other. If that is the case, the feature representing the dominant real-world object is retained and the other feature is deleted.
If one of the original real-world objects is not clearly dominant, the following considerations are used as a guideline to determine whether a feature is retained:
Is the function of the resultant real-world object the same as one of the originals?
Can one of the original real-world objects be considered the obvious predecessor to the resultant real-world object?
Is the area of the resultant real-world object less than twice that of one of the original real-world objects?
If the continuation of the feature cannot be justified on one or more of these grounds, all the original features are deleted and replaced with new features.
Two fields, one of which is larger than the other, are merged into one, such that the resultant real- world object is recognisable as the larger field subsuming the smaller field. The feature representing the larger field is retained. The smaller field feature is deleted.
Three fields, which are broadly similar in size, are merged into one, such that none of the original fields are recognisable as the obvious predecessor of the resultant field. The original features are deleted, and a new feature is created to represent the field.
A pond within a field is filled in. The feature representing the pond is deleted and the field feature is retained.
Two semi-detached cottages of equal size are combined into one dwelling, with no alteration to the external geometry of the building. Both of the original features are deleted, and a new feature is created.
A large greenhouse lies within a parcel of land only marginally larger than itself. The greenhouse is demolished. The feature representing the greenhouse is deleted, and the feature representing the land parcel is deleted as it has increased significantly and can no longer be considered as the same object.
When a real-world object represented by a polygon feature changes such that the nature of the feature changes, the feature is retained, unless changes to its geometry indicate deletion of the feature under the guidelines above.
An area of agricultural land is wholly planted with trees; there are no changes to its bounding features. The descriptive group of the feature changes but its geometry is unchanged. The feature is retained.
An area of woodland is felled, and the area now consists of rough grass and scrub. The feature is retained.
A barn is converted into a private dwelling. There is no change to the nature of the building (it is still a building) and the feature is retained.
When a polygon feature is changed solely to correct errors either in geometry or other attributes, the feature is retained. If the feature has been moved to correct an error and simultaneously modified for real-world change; for example, when natural movement of a physical feature occurs, such as a riverbank or foreshore, then the feature modification rules above are followed.
A line feature representing an old fence is found to have an error in its position and is corrected. The line feature and the polygon features bounded by it are retained. The version numbers of the features are incremented.
The feature representing an area of road has been assigned an incorrect descriptive group. The feature is reclassified and retained. The feature version number is incremented.
An area of non-coniferous trees has been incorrectly assigned the descriptive term 'coniferous trees' by photogrammetric revision techniques. The feature is reclassified and retained. The feature version number is incremented.
A building foundation captured as a feature with a descriptive group of ‘unclassified’ is completed, and the feature is reclassified to a descriptive group of ‘building’. The feature is retained. The feature version number is incremented.
A feature is no longer included within Ordnance Survey’s capture specification. The feature is not retained.
Within OS MasterMap Topography Layer, there are four topological structuring layers that determine how features interact with each other. A structuring layer contains features that do not cut across each other and are permitted to connect to each other spatially, sharing common geometry at their edges.
Most topographic features participate in a single topological structuring layer, but features that are underground or above cartographic level, or that represent pylons, cliffs and slopes are not considered to interact with other features in the topography structuring layer.
During capture and maintenance of the data, processes ensure that vertices of the geometry of features are coincident where they should be, so that the features topologically structure with each other. The full structuring layer definitions are given in the following table:
Structuring layer | Rule |
---|---|
OS MasterMap Topography Layer is supplied as a national vector tiles set in six MBTiles files (one file per feature type). This is a lightweight set of tiles that is efficient and fast to render in your software, and which provides high-resolution data and gives a seamless experience when zooming in and out. The data is supplied in Web Mercator projection (ESPG:3857).
The vector tiles schema is detailed in the following table. In the zoom levels columns within the table, the letter N indicates that the specified layer and attribute are not mapped within that zoom level, whereas the letter Y indicates that the specified layer and attribute are mapped within that zoom level.
The zoom level is a number that defines how large or small the contents of a vector tiles dataset appear in the viewing pane of a GIS application.
Attribute | Zoom level: 0 to 15 | Zoom level: 16 |
---|
Attribute | Zoom level: 0 to 15 | Zoom level: 16 |
---|
The naming of attributes will be different between the various formats due to the differing naming conventions associated with each format (for example, presence of underscores, character limitations and capitalisation). Therefore, the following tables map the differing format attribute names to one another for each feature type.
Please note that the 'fid' attribute in the GeoPackage format does not align to the 'fid' attribute in the GML format. In GeoPackage, 'fid' is a mandatory field that is procedurally generated, with a non-persistent number, when the format is produced. In GML, the 'fid' attribute houses the feature's unique TOID.
GeoPackage | Vector tiles | GML |
---|
OS MasterMap Topography Layer is supplied as six GeoPackage files (one file per feature type) for a user- defined area of interest (AOI) only. GeoPackage (*.gpkg) is an open, standard, non-proprietary, platform- independent data format for geographic information systems (GIS), as defined by the Open Geospatial Consortium (OGC). It is designed to be a lightweight format that can contain large amounts of varied and complex data in a single, easy to distribute and ready to use file. GeoPackage is natively supported by numerous software applications.
GeoPackage offers users the following benefits:
The files are easy to transfer and offer the end-user a rich experience.
Attribute names are not limited in length, making the format user-friendly.
The file size limit is very large at 140 TB, so lots of data can be easily accommodated (please note that a file size limit may be imposed by the file system to which the file is written).
It supports raster, vector, and database formats, making it a highly versatile solution.
It is an OGC standard.
In most cases, it is a plug-and-play format.
For information on how to open, use and understand a GeoPackage dataset, please refer to our . Further detailed information on GeoPackage can be found on the .
It is not recommended that users download large AOIs of OS MasterMap Topography Layer in GeoPackage format as this will be too large a file for the majority of GIS to handle.
The OS MasterMap Topography Layer product is supplied in Geography Markup Language (GML) version 2.1.2. This section describes how OS MasterMap is defined in GML. An understanding of XML
(eXtensible Mark-up Language) and XML schemas is required. The XML specifications that GML is based on are available from the .
XML schemas are used to validate the format and content of the GML. The GML 2.1.2 specification provides a set of schemas that define the GML feature constructs and geometric types. These are designed to be used as a basis for building application-specific schemas, which define the data content.
The Ordnance Survey application schemas that are referenced by the data are available from the .
These schemas make use of XML Schema Definitions (XSDs) and Document Type Definitions (DTDs) produced by the W3C that are available from .
Some recent parsers now fail to validate OS MasterMap Topography Layer using these schemas as working practices and XML schema specification clarifications have led to GML 2.1.2 being rendered invalid.
The W3C-provided XSDs and DTDs are:
xml.xsd – To allow the use of the xml:lang attribute for language qualification.
XMLSchema.dtd – Required by xml.xsd.
datatypes.dtd – Required by XMLSchema.dtd.
The OGC-provided schemas are:
feature.xsd – The feature and property constructs.
geometry.xsd – The geometric constructs, such as polygon and point.
xlinks.xsd – A schema based on the W3C XLINK recommendation provided by the OGC to make use of the XLINK constructs.
The Ordnance Survey application schemas are:
OSDNFFeatures.xsd – The definition of the Ordnance Survey features and their properties.
OSComplexTypes.xsd – The complex property types, including changeHistoryType.
OSSimpleTypes.xsd – The basic property types, including descriptiveGroupType and accuracyOfPositionType.
OSMeasures.xsd – The definition of measure-qualified types used in OS MasterMap data.
OSQueryresult.xsd – The definition of a query result with its properties.
OSGeometryTopology.xsd – Geometry and topology extensions to the GML 2.1.2 specification required by Ordnance Survey, including rectangles and polygon topology.
Any examples in this section that mention specific data content are to be taken as examples only. All data content is defined in OS MasterMap Topography Layer separately, and the examples are not necessarily in harmony with the data specification.
The XML declaration to all query results is: <?xml version=‘1.0’ encoding=‘UTF-8’?>
All information returned from a query is provided in an osgb:FeatureCollection. If no features lie inside a query, then an empty collection is returned with its required collection properties.
The document defines the XML namespaces:
For example:
The gml:description element is the first property of the feature collection; this contains a copyright statement and the date of the query.
The gml:boundedBy element is the next property of the feature collection; this contains a gml:null element with the value of ‘unknown’.
The start time of the query is specified at GMT as a feature property. The name of the property is queryTime.
The following optional properties are provided for the osgb:FeatureCollection if they were provided as part of the query. The ordering of these properties is according to the order they appear in the table:
For geographically chunked data, if there are features in the collection, the last element in the feature collection is an osgb:boundedBy element. This is a gml:Box defining the minimum bounding rectangle of all items in the collection, including the query extent. If the collection is empty, no osgb:boundedBy element is provided.
For example:
Each feature within the osgb:FeatureCollection is encapsulated in one of the following member elements according to its feature type:
Each member element contains a single feature element that has the name of the feature type, for example, TopographicPoint, TopographicLine, and so on.
The TOID of the feature is provided in the XML attribute ‘fid’ of the osgb:Feature element. A TOID has a maximum of 16 digits and is prefixed with ‘osgb’. The ‘osgb’ prefix is required to form a valid XML ID type.
A feature element does not contain a name, description or boundedBy element. For example:
Our application schema defines three main types of properties that are present inside a feature element; these are simple, complex and geometric properties.
The ordering of properties within a feature element is important as XML validation is reliant on elements being in a specified order. The order of properties is specified within the XML schema.
Each type of property may additionally have associated metadata encoded using an XML attribute. This metadata provides some qualification of the status or accuracy of the content provided in the attribute.
A simple property is one that contains a single piece of non-geometric information. These properties correspond to simple feature attributes. The value of each feature attribute is enclosed in an element that takes its name from the feature attribute.
A feature association is a special type of simple property that defines a relationship between one feature and another. The feature association is defined by the XML attribute xlink:href. This shall refer to a feature as if it was locally available, even though this is not guaranteed to be the case; that is, it shall be set to the character ‘#’ followed by ‘osgb’ and then the TOID of the feature being referenced.
For example:
A geometric property is one that describes a specific geometry. All geometric properties are encoded according to the GML specification. We have extended the GML v.2.1.2 specification to include a rectangle that is defined by two points. The first point defines the minimum coordinate, whilst the second point defines the maximum coordinate.
All geometric properties are encoded by placing the GML geometry elements inside an element that takes its name from the feature attribute.
The XML attribute srsName shall be set to ‘osgb:BNG’ (BNG stands for British National Grid), which uses eastings and northings specified in metres.
If a line is broken or a polygon has bled into another because of a partial update (see inconsistent features), then the XML attribute broken shall be set to ‘true’. A line that is broken will be encoded as a gml:MultiLineString.
All polygon outer boundaries have an anticlockwise orientation, and all inner boundaries have a clockwise orientation.
For example:
A complex property is one that contains more than one piece of information. These properties correspond to the complex feature attributes.
Class model
The definition of a complex property here is recursive, so complex properties may be nested. Currently, within OS MasterMap, this recursion is not used.
Figure 9: Class model diagram showing a complex property in OS MasterMap Topography Layer.
XML mapping
The complex property element takes its name from the complex feature attribute. Each part of a complex property shall be encoded as a simple, complex, geometry or topology property, as appropriate, inside the complex property element.
For example:
Feature type format | GeoPackage | Vector tiles | GML |
---|
Here are the dates when OS MasterMap Topography Layer was previously refreshed and links to the release notes:
Publication date | Extraction date |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
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5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
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5km Tile | OS Grid Reference | Coordinates (OSGB36) |
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5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
5km Tile | OS Grid Reference | Coordinates (OSGB36) |
---|
Attribute | Zoom level: 0 to 15 | Zoom level: 16 |
---|
Attribute | Zoom level: 0 to 15 | Zoom level: 16 |
---|
Attribute | Zoom level: 0 to 15 | Zoom level: 16 |
---|
Attribute | Zoom level: 0 to 15 | Zoom level: 16 |
---|
GeoPackage | Vector tiles | GML |
---|
GeoPackage | Vector tiles | GML |
---|
GeoPackage | Vector tiles | GML |
---|
GeoPackage | Vector tiles | GML |
---|
GeoPackage | Vector tiles | GML |
---|
Feature type format | GeoPackage | Vector tiles | GML |
---|
xlink –
gml –
osgb –
xml –
osgb – The location of the schema is defined as: The fid is set to the Ordnance Survey identifier given to the query.
Name | Type | Format | Description |
---|
Member element | Feature type |
---|
Topography
Feature Type = ‘TopographicLine’ or ‘TopographicArea’ descriptiveGroup not equal to ‘Landform’
physicalLevel = ‘50’
physicalPresence = ‘Closing’, ‘Edge/Limit’, ‘Obstructing’, ‘Overhead’ or ‘Moveable’
Landform
Feature Type = ‘TopographicLine’ or ‘TopographicArea’ descriptiveGroup = ‘Landform’
physicalPresence = ‘Closing’, ‘Edge/Limit’, ‘Obstructing’ or ‘Overhead’
Pylons
Feature Type = ‘TopographicLine’ or ‘TopographicArea’ physicalLevel = ‘51’
physicalPresence = ‘Closing’, ‘Edge/Limit’, ‘Obstructing’ or ‘Overhead’
Boundaries
Feature Type = ‘BoundaryLine’ or ‘CartographicSymbol’ descriptiveGroup = ‘Political Or Administrative’
toid | N | Y |
theme | N | Y |
style_code | N | Y |
style_description | N | Y |
line | N | Y |
toid | N | Y |
theme | N | Y |
orientation | N | Y |
style_code | N | Y |
style_description | N | Y |
point | N | Y |
toid | N | Y |
theme | N | Y |
height | N | Y |
style_code | N | Y |
style_description | N | Y |
colour_code | N | Y |
font_code | N | Y |
rotation | N | Y |
geo_x | N | Y |
geo_y | N | Y |
anchor | N | Y |
text_string | N | Y |
point | N | Y |
toid | N | Y |
theme | N | Y |
style_code | N | Y |
style_description | N | Y |
polygon | N | Y |
toid | N | Y |
style_code | N | Y |
style_description | N | Y |
line | N | Y |
toid | N | Y |
theme | N | Y |
style_code | N | Y |
style_description | N | Y |
point | N | Y |
fid | N/A | N/A |
toid | toid | fid |
feature_code | N/A | featureCode |
version | N/A | version |
version_date | N/A | versionDate |
theme | theme | theme |
accuracy_of_position | N/A | accuracyOfPosition |
change_date | N/A | changeDate |
reason_for_change | N/A | reasonForChange |
descriptive_group | N/A | descriptiveGroup |
descriptive_term | N/A | descriptiveTerm |
physical_level | N/A | physicalLevel |
physical_presence | N/A | physicalPresence |
style_description | style_description | N/A |
style_code | style_code | N/A |
fid | N/A | N/A |
toid | toid | fid |
feature_code | N/A | featureCode |
version | N/A | version |
version_date | N/A | versionDate |
theme | theme | theme |
change_date | N/A | changeDate |
reason_for_change | N/A | reasonForChange |
descriptive_group | N/A | descriptiveGroup |
descriptive_term | N/A | descriptiveTerm |
orientation | orientation | orientation |
physical_level | N/A | physicalLevel |
physical_presence | N/A | physicalPresence |
reference_to_feature | N/A | N/A |
style_code | style_code | N/A |
style_description | style_description | N/A |
fid | N/A | N/A |
toid | toid | fid |
feature_code | N/A | featureCode |
version | N/A | version |
version_date | N/A | versionDate |
theme | theme | theme |
change_date | N/A | changeDate |
reason_for_change | N/A | reasonForChange |
descriptive_group | N/A | descriptiveGroup |
descriptive_term | N/A | descriptiveTerm |
make | N/A | make |
physical_level | N/A | physicalLevel |
physical_presence | N/A | physicalPresence |
anchor_position | N/A | anchorPosition |
font | N/A | font |
height | height | height |
orientation | N/A | orientation |
text_string | text_string | textString |
style_description | style_description | N/A |
style_code | style_code | N/A |
colour_code | colour_code | N/A |
font_code | font_code | N/A |
rotation | rotation | N/A |
geo_x | geo_x | N/A |
geo_y | geo_y | N/A |
anchor | anchor | N/A |
fid | N/A | N/A |
toid | toid | fid |
feature_code | N/A | featureCode |
version | N/A | version |
version_date | N/A | versionDate |
theme | theme | theme |
calculated_area_value | N/A | calculatedAreaValue |
change_date | N/A | changeDate |
reason_for_change | N/A | reasonForChange |
descriptive_group | N/A | descriptiveGroup |
descriptive_term | N/A | descriptiveTerm |
make | N/A | make |
physical_level | N/A | physicalLevel |
physical_presence | N/A | physicalPresence |
style_description | style_description | N/A |
style_code | style_code | N/A |
fid | N/A | N/A |
toid | toid | fid |
feature_code | N/A | featureCode |
version | N/A | version |
version_date | N/A | versionDate |
theme | N/A | theme |
accuracy_of_position | N/A | accuracyOfPosition |
change_date | N/A | changeDate |
reason_for_change | N/A | reasonForChange |
descriptive_group | N/A | descriptiveGroup |
descriptive_term | N/A | descriptiveTerm |
non_bounding_line | N/A | nonBoundingLine |
height_above_datum | N/A | heightAboveDatum |
accuracy_of_height_above_datum | N/A | accuracyOfHeightAboveDatum |
height_above_ground_level | N/A | heightAboveGroundLevel |
accuracy_of_height_above_ground_level | N/A | accuracyOfHeightAboveGround |
make | N/A | make |
physical_level | N/A | physicalLevel |
physical_presence | N/A | physicalPresence |
style_description | style_description | N/A |
style_code | style_code | N/A |
fid | N/A | N/A |
toid | toid | fid |
feature_code | N/A | featureCode |
version | N/A | version |
version_date | N/A | versionDate |
theme | theme | theme |
accuracy_of_position | N/A | accuracyOfPosition |
change_date | N/A | changeDate |
reason_for_change | N/A | reasonForChange |
descriptive_group | N/A | descriptiveGroup |
descriptive_term | N/A | descriptiveTerm |
height_above_datum | N/A | heightAboveDatum |
accuracy_of_height_above_datum | N/A | accuracyOfHeightAboveDatum |
height_above_ground_level | N/A | heightAboveGroundLevel |
accuracy_of_height_above_ground_level | N/A | accuracyOfHeightAboveGround |
make | N/A | make |
physical_level | N/A | physicalLevel |
physical_presence | N/A | physicalPresence |
style_description | style_description | N/A |
style_code | style_code | N/A |
Boundary Line | MultiLineString | line | GM_MULTICURVE (MULTILINE) |
Cartographic Symbol | Point | point | GM_POINT (POINT) |
Cartographic Text | Point | point | GM_POINT (POINT) |
Topographic Area | Polygon | polygon | GM_SURFACE (POLYGON) |
Topographic Line | MultiLineString | line | GM_MULTICURVE (POLYLINE) |
Topographic Point | Point | point | GM_POINT (POINT) |
queryExtent | Geometric property | gml:Polygon or osgb:Rectangle (see Geometry). | The query extent provided as part of a spatial query. |
queryChangeSinceDate | Date | CCYY-MM-DD | The date that was given as part of a change-only query. |
boundaryMember | BoundaryLine |
cartographicMember | CartographicText, CartographicSymbol |
topographicMember | TopographicPoint, TopographicLine, TopographicArea |
departedMember | DepartedFeature (see section on COU) |
Boundary Line | MultiLineString | line | GM_MULTICURVE (MULTILINE) |
Cartographic Symbol | Point | point | GM_POINT (POINT) |
Cartographic Text | Point | point | GM_POINT (POINT) |
Topographic Area | Polygon | polygon | GM_SURFACE (POLYGON) |
Topographic Line | MultiLineString | line | GM_MULTICURVE (POLYLINE) |
Topographic Point | Point | point | GM_POINT (POINT) |
NS4505 | NS 47825 05240 | 247790.7, 605224.0 |
NX3540 | NX 37464 41871 | 237419, 541979 |
NX6550 | NX 68975 51146 | 268968, 551139 |
NS4505 | NS 47825 05240 | 247790.7, 605224.0 |
NX3540 | NX 37464 41871 | 237419, 541979 |
NX6550 | NX 68975 51146 | 268968, 551139 |
NS4505 | NS 47825 05240 | 247790.7, 605224.0 |
NX3540 | NX 37464 41871 | 237419, 541979 |
NX6550 | NX 68975 51146 | 268968, 551139 |
NS4505 | NS 47825 05240 | 247790.7, 605224.0 |
NX3540 | NX 37464 41871 | 237419, 541979 |
NX6550 | NX 68975 51146 | 268968, 551139 |
NS4505 | NS 47825 05240 | 247790.7, 605224.0 |
NX3540 | NX 37464 41871 | 237419, 541979 |
NX6550 | NX 68975 51146 | 268968, 551139 |
NS4505 | NS 47825 05240 | 247790.7, 605224.0 |
NX3540 | NX 37464 41871 | 237419, 541979 |
NX6550 | NX 68975 51146 | 268968, 551139 |
NS4505 | NS 47825 05240 | 247790.7, 605224.0 |
NX3540 | NX 37464 41871 | 237419, 541979 |
NX6550 | NX 68975 51146 | 268968, 551139 |
NS4505 | NS 47825 05240 | 247790.7, 605224.0 |
NX3540 | NX 37464 41871 | 237419, 541979 |
NX6550 | NX 68975 51146 | 268968, 551139 |
NS4505 | NS 47825 05240 | 247790.7, 605224.0 |
NX3540 | NX 37464 41871 | 237419, 541979 |
NX6550 | NX 68975 51146 | 268968, 551139 |
NS4505 | NS 47825 05240 | 247790.7, 605224.0 |
NX3540 | NX 37464 41871 | 237419, 541979 |
NX6550 | NX 68975 51146 | 268968, 551139 |
04 November 2024 | 17 October 2024 |
23 September 2024 | 05 September 2024 |
12 August 2024 | 25 July 2024 |
24 June 2024 | 06 June 2024 |
13 May 2024 | 25 April 2024 |
02 April 2024 | 14 March 2024 |
19 February 2024 | 01 February 2024 |
04 January 2024 | 14 December 2023 |
20 November 2023 | 02 November 2023 |
09 October 2023 | 20 September 2023 |
The table below shows our future schedule of extraction and publication dates for OS MasterMap Topography Layer. We aim to keep this schedule up to date, but you should treat these dates as a guide only as they are subject to change. The extraction date will be confirmed on the publication date.
Please note these dates only apply to bespoke polygons, 'area of interest' orders and national sets.
Publication date | Extraction date |
---|---|
This product is available to try out online using one of our three sets of sample data (Exeter, Newport and Inverness) through the OS MasterMap product viewer:
This table gives descriptions for each feature code value. The feature code itself is arbitrarily assigned and so carries no information without this table.
In the 'Descriptive term' column, a blank box means multiple, other, or none. This code is used for features with multiple descriptive terms, with no descriptive term, or with one descriptive term that does not have its own feature code.
The column 'Feature type' has been abbreviated by omitting the words topographic, boundary and cartographic from the feature type names. Where ‘Line’ appears in this column, it includes both TopographicLine and BoundaryLine Feature Types.
Descriptive group | Feature type | Descriptive term | Feature code |
---|---|---|---|
16 December 2024
28 November 2024
03 February 2025
16 January 2025
17 March 2025
27 February 2025
Building
Area
N/A
10021
Building
Line
N/A
10017
Building
Point
N/A
10022
Building
Symbol
N/A
10016
Building
Text
N/A
10020
Building
Line
Division
10018
Building
Line
Outline
10019
Buildings Or Structure
Area
N/A
10025
Buildings Or Structure
Line
N/A
10023
Buildings Or Structure
Point
N/A
10024
Buildings Or Structure
Symbol
N/A
10027
Buildings Or Structure
Text
N/A
10026
Buildings Or Structure
Text
Compound
10028
Built Environment
Area
N/A
10031
Built Environment
Line
N/A
10032
Built Environment
Point
N/A
10029
Built Environment
Symbol
N/A
10030
Built Environment
Text
N/A
10034
Built Environment
Text
Compound
10033
General Feature
Area
N/A
10044
General Feature
Line
N/A
10046
General Feature
Point
N/A
10045
General Feature
Symbol
N/A
10042
General Feature
Text
N/A
10043
General Feature
Point
Positioned Boulder
10051
General Feature
Point
Positioned Coniferous Tree
10050
General Feature
Point
Positioned Nonconiferous Tree
10048
General Feature
Line
Tunnel Edge
10041
General Surface
Area
N/A
10056
General Surface
Line
N/A
10052
General Surface
Point
N/A
10057
General Surface
Symbol
N/A
10055
General Surface
Text
N/A
10059
General Surface
Area
Multi Surface
10053
General Surface
Area
Step
10054
General Surface
Line
Step
10058
Glasshouse
Area
N/A
10062
Glasshouse
Line
N/A
10064
Glasshouse
Point
N/A
10063
Glasshouse
Symbol
N/A
10061
Glasshouse
Text
N/A
10060
Height Control
Area
N/A
10065
Height Control
Line
N/A
10071
Height Control
Point
N/A
10068
Height Control
Symbol
N/A
10070
Height Control
Text
N/A
10069
Height Control
Point
Bench Mark
10067
Height Control
Symbol
Bench Mark
10066
Historic Interest
Area
N/A
10076
Historic Interest
Line
N/A
10075
Historic Interest
Point
N/A
10080
Historic Interest
Symbol
N/A
10073
Historic Interest
Text
N/A
10074
Historic Interest
Text
Compound
10077
Historic Interest
Point
Site Of Heritage
10072
Inland Water
Area
N/A
10089
Inland Water
Line
N/A
10087
Inland Water
Point
N/A
10088
Inland Water
Symbol
N/A
10084
Inland Water
Text
N/A
10090
Inland Water
Text
Compound
10086
Inland Water
Line
Culvert
10092
Inland Water
Point
Culvert
10085
Inland Water
Symbol
Culvert
10091
Inland Water
Symbol
Direction Of Flow
10082
Inland Water
Line
Tunnel Edge
10083
Landform
Area
N/A
10093
Landform
Line
N/A
10095
Landform
Point
N/A
10094
Landform
Symbol
N/A
10106
Landform
Text
N/A
10102
Landform
Line
Bottom Of Cliff
10103
Landform
Line
Bottom Of Slope
10097
Landform
Area
Cliff
10099
Landform
Text
Compound
10105
Landform
Point
Disused Feature
10100
Landform
Line
Ridge Or Rock Line
10101
Landform
Area
Slope
10096
Landform
Line
Top Of Cliff
10104
Landform
Line
Top Of Slope
10098
Natural Environment
Area
N/A
10111
Natural Environment
Line
N/A
10110
Natural Environment
Point
N/A
10109
Natural Environment
Symbol
N/A
10108
Natural Environment
Text
N/A
10107
Network Or Polygon Closing Geometry
Area
N/A
10116
Network Or Polygon Closing Geometry
Line
N/A
10115
Network Or Polygon Closing Geometry
Point
N/A
10118
Network Or Polygon Closing Geometry
Symbol
N/A
10117
Network Or Polygon Closing Geometry
Text
N/A
10112
Network Or Polygon Closing Geometry
Line
Inferred Property Closing Link
10114
Network Or Polygon Closing Geometry
Line
Polygon Closing Link
10113
Path
Area
N/A
10123
Path
Line
N/A
10124
Path
Point
N/A
10120
Path
Symbol
N/A
10121
Path
Text
N/A
10122
Path
Area
Step
10119
Path
Line
Tunnel Edge
10125
Political Or Administrative
Area
N/A
10126
Political Or Administrative
Line
N/A
10137
Political Or Administrative
Point
N/A
10132
Political Or Administrative
Symbol
N/A
10134
Political Or Administrative
Text
N/A
10133
Political Or Administrative
Symbol
Boundary Half Mereing
10130
Political Or Administrative
Point
Boundary Post Or Stone
10129
Political Or Administrative
Line
County
10127
Political Or Administrative
Line
District
10131
Political Or Administrative
Line
Electoral
10128
Political Or Administrative
Line
Parish
10136
Political Or Administrative
Line
Parliamentary
10135
Rail
Area
N/A
10167
Rail
Line
N/A
10155
Rail
Point
N/A
10159
Rail
Symbol
N/A
10161
Rail
Text
N/A
10166
Rail
Line
Buffer
10160
Rail
Text
Compound
10156
Rail
Line
Narrow Gauge
10164
Rail
Line
Standard Gauge
10162
Rail
Line
Standard Gauge Track
10163
Rail
Point
Structure
10158
Rail
Symbol
Switch
10165
Rail
Line
Tunnel Edge
10157
Road Or Track
Area
N/A
10172
Road Or Track
Line
N/A
10175
Road Or Track
Point
N/A
10176
Road Or Track
Symbol
N/A
10170
Road Or Track
Text
N/A
10171
Road Or Track
Line
Public
10168
Road Or Track
Text
Road Name Or Classification
10169
Road Or Track
Symbol
Road Related Flow
10177
Road Or Track
Line
Tunnel Edge
10173
Roadside
Area
N/A
10183
Roadside
Line
N/A
10180
Roadside
Point
N/A
10182
Roadside
Symbol
N/A
10181
Roadside
Text
N/A
10178
Roadside
Point
Structure
10179
Structure
Area
N/A
10185
Structure
Line
N/A
10195
Structure
Point
N/A
10186
Structure
Symbol
N/A
10194
Structure
Text
N/A
10184
Structure
Area
Archway
10190
Structure
Line
Network Closing Link
10188
Structure
Area
Pylon
10193
Structure
Line
Pylon
10189
Structure
Point
N/A
10192
Structure
Point
Structure
10191
Structure
Area
Upper Level Of Communication
10187
Terrain And Height
Area
N/A
10199
Terrain And Height
Line
N/A
10201
Terrain And Height
Point
N/A
10200
Terrain And Height
Symbol
N/A
10196
Terrain And Height
Text
N/A
10198
Terrain And Height
Point
Air Height
10202
Terrain And Height
Point
Spot Height
10197
Tidal Water
Area
N/A
10210
Tidal Water
Line
N/A
10208
Tidal Water
Point
N/A
10209
Tidal Water
Symbol
N/A
10206
Tidal Water
Text
N/A
10204
Tidal Water
Text
Compound
10207
Tidal Water
Area
Foreshore
10203
Tidal Water
Text
Foreshore
10205
Tidal Water
Line
Mean High Water (Springs)
10211
Tidal Water
Line
Mean Low Water (Springs)
10212
Unclassified
Area
N/A
10217
Unclassified
Line
N/A
10216
Unclassified
Point
N/A
10215
Unclassified
Symbol
N/A
10214
Unclassified
Text
N/A
10213
This section defines the default styles for the presentation of data within OS MasterMap. This specifies the colours, fonts, symbols and line styles used for visual display and printing of OS MasterMap. The styles are defined using Scalable Vector Graphics (SVG) syntax.
See W3C SVG Working Group for information on SVG. The Cartographic styling section provides the required information to apply the styles of this section to features.
These definitions cover data supplied to customers as part of OS MasterMap by Ordnance Survey.
A style is not provided for all of the information in OS MasterMap due to limitations of generic styling and cartographic information available for specific feature types.
All coordinates in this section are specified in eastings and northings in units of metres in the British National Grid.
Stroke widths and text sizes are also specified in units of metres on the ground.
Ordnance Survey has chosen to use colours that are consistent in the internet environment. The colours used are defined with both their RGB and hexadecimal values in the colour palette.
The fonts selected by Ordnance Survey to display text are those that are commonly used with web browsers. A brief description as to how a font is used in SVG is given in the Fonts section.
There are two different uses of symbols as defined in the following sections. A base symbol set is defined in Shared symbol geometry section; these may be aggregated to form compound symbols as defined in Compound symbols. Patterns formed from repeating symbols on a predefined grid are specified in Pattern definitions.
Point symbols are used to represent the position of particular features within the data, such as a telephone call box or bollard. The symbol represents the location and type of feature.
Point symbols are applied to the visual representation by translating them to the location of the feature they are representing and rotating them, if the orientation attribute is present, by a given amount.
Fill symbols are used to represent some attribution of a polygon feature and are distributed as a pattern fill across the polygon. For example, the symbol may represent information about the topographic surface such as the vegetation type.
Because of the overheads of applying pattern fills in many current software systems, pattern fills are optional and depend on user requirements and system capabilities. For example, if a user does not require each mixed vegetation type to be identified graphically, the multiVegetationPattern (as defined in Pattern definitions) could be used to represent all mixed vegetation features.
Line styles are used to allow a user to distinguish between different types of linear feature, for example, distinctions may be made to emphasise:
Obstructing detail
Non-obstructing detail
Underground detail
Overhead detail
Building outlines
Water limits and linear features
Landform detail
Narrow-gauge railways
Statutory boundaries
Polygon-closing features
Some lines, particularly those representing the road network, are drawn twice, using first a background style and then an overlay to achieve a multicoloured result. Styles have been defined in this way to produce effects like lines with outlines. This section defines the two components as separate styles. For example, a minor road is first drawn as a black background (carriagewayOutline) that is then overlain with a yellow foreground (minorRoadLine) as below:
The line styles are defined in Line styles.
The gml2svg.xsl declares the use of the Arial font for Ordnance Survey’s standard depiction of text string. Within the XSL file, the text colour is dictated by the descriptiveGroup, as is the use of italics. The textRendering complex attribute for a CartographicText feature contains information on the placement, orientation and height for rendering the text.
A font value of 0, 1, 2, or 3 as used in Land-Line® is also provided that can optionally be used for depiction. The suggested fonts for cartographic display are:
– Lutheran (used for non-Roman antiquities)
– Normal – medium Roman font
– Light Roman font (used primarily for building numbers, Roman antiquities, and some administrative names particularly in 1:10 000 areas)
– Suppressed text not supplied in Land-Line due to space limitations.