The 1:25 000 Scale Colour Raster data product mirrors the popular OS Explorer Map series, showing a detailed overview of environmental and leisure features across Great Britain. It can provide the ideal mapping backdrop upon which to overlay business information. The 1:25 000 Scale Colour Raster’s backdrop can then be overlaid with other Ordnance Survey vector products or a customer’s own geographic / business data; it can also provide a useful background map in its own right.

Screen images can be plotted to produce a high-quality map. An example of the data is shown below.

Product applications

1:25 000 Scale Colour Raster is aimed at professional / business markets and its graphic specification can aid with the following:

• Environmental applications

• Leisure applications

• Construction

• Engineering

• Planning and licence applications

• Farm / estate / property management

• Real estate

To be able to view each TIFF tile in correct geographic relation to the National Grid and to other tiles, the tiles must be georeferenced. Geographic information systems (GIS) typically provide georeferencing as part of their functionality, but for each set of tiles, it is necessary to provide the information on how the tiles should be ordered.

Ordnance Survey provides this information in a set of georeferencing files, also known as world files. A complete set of georeferencing files for 1:25 000 Scale Colour Raster is available on the 1:25 000 Scale Colour Raster Downloads page.

There are several different types of world file. Prior to downloading one of the sets, customers are advised to check with their system suppliers to find out which type of world file their system supports.

The conventions behind the files’ creation can be found in the product's technical specification. By using the conventions outlined there, this means that other datasets using the same conventions can be imported into the same GIS to add value to the raster map; for example, overlaying a routing or logistics network over the map or displaying a customer’s demographic information.

The georeferencing files should be saved in the same directory as the files of the map tiles themselves.

Settlements and man-made structures

Buildings are generalised and shown with colour tint and cartographically placed text to indicate settlement name and extent.

Structures are indicated by lines, buildings or symbols, and selected distinctive named features are supplemented with a text description.

Transport

Transport features depicted include tracks, paths, roads, railway lines (single and multiple track), railway stations, airports and airstrips, ferry routes and ports, cycle routes, and bus and coach stations.

Water features

Water features are shown in blue with associated text. A distinction is made between natural (blue) and man-made (black) water features, except for canals (which are shown in blue).

Natural landscape features

Different types of natural features and vegetation are shown by symbols or colour tint, including woods, rock, scree, boulders, sand, shingle, mud and slope.

Rights of way and access land

The following routes are depicted in this product:

• Footpaths, including permissive

• Bridleways, including permissive

• Byways open to all traffic

• Restricted byways

• Other routes with public access (ORPA)

• National Trails and Scottish Great Trails and Recreational Routes

• Recreational routes

• Rights of way (England and Wales only)

• Access land

Portrayal of access land is intended as a guide to land that is normally available for access on foot, for example, access land created under the Countryside and Rights of Way Act 2000, and land managed by The National Trust™, Woodland Trust, National Parks and local authorities. Land owned by Forestry England is only shown as Open Access where coincident with CRoW land.

Height

Ground contours, survey heights and air survey heights are depicted. Heights are to the nearest metre above mean sea level. Heights shown close to a triangulation pillar refer to the ground level height at the pillar and not necessarily the height at the summit.

Administrative boundaries

National, county, district, unitary authority and civil parish boundaries are all depicted in the product.

Tourist information

Selected tourist and leisure information is normally restricted to features providing public access or services. Tourist information is shown by a blue symbol using, where possible, nationally recognised symbols. Where appropriate, symbols also have black distinctive names, for example, country parks, major gardens and so on.

Heritage and archaeological sites

Depiction includes information supplied by English Heritage®, the Royal Commission on the Ancient and Historical Monuments of Scotland, and the Royal Commission on the Ancient and Historical Monuments of Wales.

Coastline and coastal features

Low and high water, man-made and natural landscape features are all depicted.

National Grid lines

National Grid lines are shown at 1-km intervals.

Annotation

Descriptive and distinctive names are depicted as text.

Source and scale of the product

1:25 000 Scale Colour Raster is derived from the source data used to create its graphic counterpart, the OS Explorer Map series. Generalisation is used to emphasise, simplify, select and sometimes omit features to produce a cartographic representation of the landscape at a scale of 1:25 000.

The nominal scale of the product is 1:25 000, but the recommended minimum-to-maximum scale range is 1:8 000 to 1:25 000 scale.

Coordinate reference system

1:25 000 Scale Colour Raster is available in National Grid coordinates, which are expressed in metres relative to an origin set to a point west of the Isles of Scilly. These coordinates can easily be spatially related to other surveys, drawings, datasets or Ordnance Survey products. A general introductory guide to the British National Grid (BNG) is available on the Ordnance Survey website.

Coverage

Coverage is Great Britain only. 1:25 000 Scale Colour Raster is supplied in standard 10 km by 10 km tiles aligned to the National Grid.

Product revision programme

1:25 000 Scale Colour Raster is updated via a revision programme. The revision programme mirrors that of the OS Explorer Map series, and is determined by assessing the following factors:

• Known surveyed change

• Change intelligence gathered from a range of sources

• How long it's been since an area was last revised

Priority is given to prestige sites categorised as significant items of change, such as major road construction projects. Significant items of surveyed change relevant to the scale are captured during the revision programme.

Where a line feature ends by intersecting the tile edge, it is matched with its corresponding feature on the adjacent tile so that both features end on the same unique coordinate. The representation of detail across the tile edge will be of a cartographically acceptable standard when plotted or displayed at scale.

Product update schedule

1:25 000 Scale Colour Raster is supplied to customers quarterly in March, June, September and December, incorporating any updates made by the revision programme.

1:25 000 Scale Colour Raster – Map symbols legend

The map symbols legend for 1:25 000 Scale Colour Raster is available to download as a PDF below.

1:25 000 Scale Colour Raster – Welsh map symbols legend

The Welsh language legend for 1:25 000 Scale Colour Raster is available as a PDF below.

Full tile list

The full tile list for 1:25 000 Scale Colour Raster is available as an excel sheet.

Change-only update (COU) tile list

The COU tile list for 1:25 000 Scale Colour Raster is available as an excel sheet.

1:25 000 Scale Colour Raster – Georeferencing (TAB files)

Download free 10km x 10km TAB files for use tih MapInfo

1:25 000 Scale Colour Raster – Georeferencing (TFW files)

Download free 10km x 10km TIFF World Files (TFW) that cn be used to georeference raster data in ESRI ArcGIS

1:25 000 Scale Colour Raster – Sea tiles (TAB)

1:25 000 Scale Colour Raster – Sea tiles (TFW)

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1:25 000 Scale Colour Raster is the digital alternative to Ordnance Survey's OS Explorer paper map series for Great Britain available in 10km square tiles. The 1:25 000 Scale Colour Raster’s backdrop can be overlaid with other Ordnance Survey vector products or a customer’s own geographic/business data or used as a standalone map.

How to get this product

Access to this product is free for Public Sector Geospatial Agreement (PSGA) Members. Find out if you are a PSGA Member or download a sample of 1:25 000 Scale Colour Raster data by accessing the product page on the OS website, which has links to all of the relevant resources. Alternatively, you can try out the full product by applying for a Data Exploration license.

Visualise 1:25 000 Scale Colour Raster data online

1:25 000 Scale Colour Raster product specification

Number of tiles in Great Britain

2 859 (edge matched)

• England: 1,508

• Scotland: 1,130

• Wales: 289

Tile size

10km by 10km

Availability

National coverage

Resolution

254 and 660 dots per inch

Data structure

Raster

Transfer formats

• TIFF PackBits compressed

• TIFF palette 8-bit (256 colours) with LZW* compression

• GeoTIFF with LZW* compression

* If LZW compressed formats are used, then registration may be required. Information is available on the Unisys® website.

Storage volumes per tile

0.2–9 Mb compressed

Update frequency

Quarterly: March, June, September and December (change-only updates)

Product legend

Maintained versions (in English and Welsh) of the 1:25 000 Scale Colour Raster legend, which defines all of the map symbols used in the product, can be found on the 1:25 000 Scale Colour Raster Downloads page.

Common mapping abbreviations used in the product

A full list of the common mapping abbreviations used in 1:25 000 Scale Colour Raster is available in the shared Colour Raster Map Technical Specification.

Additional technical information

Additional information, common to all colour raster map products is available through the Colour Raster Map Core principle pages. These pages provide an overview of the product and a technical specification covering:

• Georeferencing

• Image file directory (TIFF)

• Product glossary