The following is a description of the features that are available in the product. A full list of feature classes and their associated attributes is given in the technical specification.

Not all features available in the product are included in the raster format. For a full list of features and their styling in the raster format please refer to the legends in the Raster specification page of the technical specification.

The GML naming of attributes is used in the main text of this guide; the naming of the attributes in shape files will be different due to the limitations of the shape file format.

Buildings

A built entity that includes a roof. This is a generalised building and could be made up of an amalgamation of other buildings and structures.

• Shapefile: Building.shp

Building Glasshouses

A building constructed largely of glass for the purposes of commercial horticulture. This is a generalised glasshouse and could be made up of an amalgamation of individual glasshouses. Only glasshouses larger than 5000 m2 are included.

• Shapefile: Glasshouse.shp

• GML FeatureType: Glasshouse

Roads

Road alignments

A road is defined as a metalled way for vehicles. A vehicle is defined as one with wheels on both sides of its body. Metalling is defined as any artificial (man-made) surface including areas of asphalt, concrete and gravel. Roads that form part of the public network and driveways to private properties that are over 100 m in length are captured. Dual carriageways are represented by centrelines when the two carriageways are closer than 32.5 m, roundabouts are represented by points when smaller than 450 m2, dead ends are removed when shorter than 36 m and roads are simplified with a 4 m tolerance.

Road alignments will have one of the following 13 classifications, each of which can be separately identified by the

‘classification’ attribute:

• ‘Motorway’

• ‘Primary Road’

• ‘A Road’

• ‘B Road’

• ‘Minor Road’

• ‘Pedestrianised Street’

• ‘Local Street’

• ‘Private Road Publicly Accessible’

• ‘Motorway, Collapsed Dual Carriageway’

• ‘Primary Road, Collapsed Dual Carriageway’

• ‘A Road, Collapsed Dual Carriageway’

• ‘B Road, Collapsed Dual Carriageway’

• ‘Minor Road, Collapsed Dual Carriageway’ Shapefile: Road.shp

• GML FeatureType: Road

Roundabouts

Roundabouts smaller than 450m2 are represented as point features, and the roads are extended to meet at the centre point. Mini roundabouts are not included.

• Shapefile: Roundabout.shp

• GML FeatureType: Roundabout

See the Technical specification for full list of roundabout ‘classification’ attribute values.

Road tunnels

Road tunnels are represented as approximate centrelines of the road that runs through the tunnel.

• Shapefile: RoadTunnel.shp

• GML FeatureType: RoadTunnel Differences between vector and raster formats:

A selection of road names and numbers are shown in the raster product, where space permits.

Motorway junctions

Point feature representing the approximate location of numbered junction on a motorway.

• Shapefile: MotorwayJunction.shp

• GML FeatureType: MotorwayJunction

Surface water

An inland waterway body sufficiently wide enough to capture as an area feature. Small lakes and small islands in waterbodies are not included.

• Shapefiles: SurfaceWater_Line.shp, SurfaceWater_Area.shp

• GML FeatureTypes: SurfaceWater_Line, SurfaceWater_Area

Tidal boundary/High and Low Water Marks

In England and Wales these tide lines will be the levels of mean tides, for example, of a tide between a spring and neap tide. In Scotland the tide lines are those of mean spring tides. In places where there is no Foreshore (for example vertical cliffs), the TidalBoundary is classified as 'High Water Mark'.

• Shapefile: TidalBoundary.shp

• GML FeatureType: TidalBoundary

Tidal water

Polygons defining the extents of tidal water, up to the High Water Mark defined by the TidalBoundaries and the Normal Tidal Limit of rivers. Tidal water is not included under bridges.

• Shapefile: TidalWater.shp

• GML FeatureType: TidalWater

Foreshore

The part of the shore or beach which lies between the Low Water Mark and High Water Mark defined by the TidalBoundaries. The same condition may exist in non-contiguous off-shore areas.

• Shapefile: Foreshore.shp

• GML FeatureType: Foreshore

Administrative boundaries

A line feature representing the limit of a government administrative area. In the event that a boundary represents the limit of more than one administrative area, classifications are applied in hierarchical order, with priority given to the largest containing area. An exception is made for National boundaries, which will be coincident with the underlying local government boundary.

The attribute ‘classification’ defines the type of boundary:

• ‘National’

• ‘District Or London Borough’

• ‘County Or Region Or Island’

• ‘Parish Or Community’

• Shapefile: AdministrativeBoundary.shp

• GML FeatureType: AdministrativeBoundary Differences between vector and raster formats:

• In the raster product only the national boundaries are depicted.

Railway tracks

All railways are represented as lines and are broken where they pass under bridges, buildings or other obstructing detail. Railway sidings and the tracks of travelling structures are not included. The attribute ‘classification’ defines the type of railway:

• ‘Multi Track’

• ‘Single Track’

• ‘Narrow Gauge’

• Shapefile: RailwayTrack.shp

• GML FeatureType: RailwayTrack

Railway tunnels

Railway tunnels are represented as approximate centrelines of the railway that runs through the tunnel.

• Shapefile: RailwayTunnel.shp

• GML FeatureType: RailwayTunnel

Railway stations

Point feature representing the buildings and platforms by a railway line where a train may stop to pick-up or drop-off goods or passengers. The attribute ‘classification’ defines the type of station:

• ‘Light Rapid Transit Station’

• ‘Railway Station’

• ‘London Underground Station’

• ‘Railway Station and London Underground Station’

• ‘Light Rapid Transit Station and Railway Station’

• ‘Light Rapid Transit Station and London Underground Station’

The name of the station is held in the attribute ‘DISTNAME’ in Shape and distinctiveName in GML.

The position of the railway station will be close to a railway alignment but will not necessarily be coincident with it.

• Shapefile: RailwayStation.shp

• GML FeatureType: RailwayStation

Functional sites

A point feature that represents the location of certain types of function or activity with appropriate attribution. The classifications are:

• Air Transport

• Education Facility - School

• Education Facility - Higher

• Medical Care

• Road Transport

• Road Services

• Water Transport

• Place Of Worship

• Leisure Centre

• Police Station

Please note:

• Only available in the vector product, functional sites include features previously supplied as ‘PublicAmenity’ and ‘Airport’ features. In previous product releases a cartographic selection was applied to these features, which is now replaced with a complete supplied set.

• Some functional sites may contain multiple sites (points) such as Educational Facility where they may have both Educational Facility – School and Educational Facility – Higher.

• Shapefile: FunctionalSite.shp

• GML FeatureType: FunctionalSite

Woodland

Areas of trees; coniferous, non-coniferous and mixed are represented as polygons. Small areas of woodland are omitted and small clearings in woodland are filled.

• Shapefile: Woodland.shp

• GML FeatureType: Woodland

Ornament

Ornament features are facsimiles of artwork, represented as a polygon, these were originally drawn on paper maps to depict coastal rocks, outcropping rocks, cartographic slopes and scree.

• Shapefile: Ornament.shp

• GML FeatureType: Ornament

Electricity transmission line

Cables used to supply electricity that is suspended between pylons.

• Shapefile: ElectricityTransmissionLine.shp

• GML FeatureType: ElectricityTransmissionLine

Named places

A representative point feature giving the general location of a settlement name or geographic place name, for the purposes of text placement.

• GML supports all the characters in the Welsh language and all names are stored in the ‘distinctiveName’ attribute. Legacy formats such as shapefile, do not support the full Welsh alphabet, therefore an alternative is provided using either the ‘DISTNAME’ or ‘HTMLNAME’ attributes.

When using the OS VectorMap District shapefile NamedPlace.shp:

• If labelling using the DISTNAME attribute, accents appear on vowels, but the Welsh consonants will have their circumflexes removed: W, w, Y, y.

• If labelling using the HTMLNAME attribute, the accents on vowels will be the same, but the Welsh consonants will be encoded using HTML escape characters, which will display correctly when displayed using software that can interpret these characters (Ŵ,ŵ,Ŷ,ŷ).

• fontHeight: the suggested height of the font is Small, Medium, Large and Extra Large

• textOrientation: the orientation of the text string in degrees clockwise from horizontal. It is held as a number between -90 and 90. This is named ORIENTATIO in Shape and textOrientation in GML

• Shapefile: NamedPlace.shp

• GML FeatureType: NamedPlace

Summit / Spot height

Point feature which in most cases represents the location of a summit of a hill or mountain, together with an elevation measurement.

• Shapefile: SpotHeight.shp

• GML FeatureType: SpotHeight

Coordinate referencing system

The vector product formats provide for the use of a variety of coordinate reference systems. At present, only the British National Grid (BNG) is used in OS VectorMap District. The BNG spatial reference system uses the OSGB36® 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.

Height datum

The BNG is a horizontal spatial reference system only; it does not include a vertical (height) reference system. In OS VectorMap District, heights are given by the ‘height’ attribute in the ‘SpotHeight’ feature. The geometric attributes therefore contain horizontal geometry only.

Currency

OS VectorMap District is derived from large-scale data, copyright 2017.

Completeness

During production many checks are undertaken to ensure that data supplied to customers are both accurate and complete. During digital manipulation in creating the data, all sources of that data are checked for conformance to specification.

These quality control checks take the form of:

• visual checks by operators;

• data testing against the product specification; and

• testing is carried out on a selection of tiles from a full national set.

Coordinate resolution

Coordinates have a precision of 1 cm and are stored to two decimal places of a metre.

This chapter describes the GML format for OS VectorMap District. It is recommended that you read this in conjunction with the Open Geospatial Consortium (OGC) document, Geography Markup Language v3.2.1.

The XML specifications that GML is based on are available from the World Wide Web Consortium (W3C®) website: http://www.w3.org.

Information about Unicode and UTF-8, the character encoding we have chosen, is available on the Unicode Consortium website: http://www.unicode.org/.

Use of examples

Any examples in this chapter that mention specific data content are to be taken as examples only.

Clarification of terms used in this chapter

Feature attribute

A property of a feature implemented as an XML element, as defined in ISO 19109.

XML attribute

Attribute as used in an XML context is referred to as an XML attribute.

Property

Most feature attributes are encoded as GML properties – property means a GML property.

Schema overview and location

XML schemas are used to define and validate the format and content of the GML. The GML v3.2 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, which are referenced by the data, are available in the product release.

These schemas make use of XSDs (XML schema definitions) and DTDs (document type definitions) produced by the W3C®, which are available from the W3C website at http://www.w3.org/XML/1998/namespace.html.

Schema descriptions

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-provided schema is:

• district.xsd – the feature type, complex type and simple type declarations.

Format description

Documentation

The ‘OSVectorMapDistrict’ schema document defines the following XML namespaces:

• district: http://namespaces.os.uk/cmd/district/v2.1

• gml: http://www.opengis.net/gml

• xsi: http://www.w3.org/2001/XMLSchema

• xlink: http://www.w3.org/1999/xlink

The location of the schema is defined as:

http://namespaces.os.uk/cmd/district/v2.1

https://os.uk/xml/cmdschema/district/v2.1/district.xsd

Features within each tile are provided in a FeatureCollection.

Simple Features Profile – Level 0

GML is designed to support a wide variety of capabilities, ranging from simple contextual mapping, such as

OS VectorMap District, to products that include complex geometric property types or even spatial and temporal topology. The Simple Features Profile of GML 3.2 defines a restricted subset of GML, allowing scope for greater interoperability.

This product conforms to Simple Features Profile – Level 0.

Geometry

A geometric property is one that describes a specific geometry. All geometric properties are encoded according to the Simple Features Profile, as referenced above.

The XML attribute ‘srsName’ shall be set to ‘urn:ogc:def:crs:EPSG::27700’, which uses eastings and northings specified in metres.

All exterior polygon boundaries have an anticlockwise orientation and all interior polygon boundaries have a clockwise orientation.

Raw GML data extract from NT VMD GML open data styled using open GIS software.

OS VectorMap District - May 2023 release note

This release note provides information about the May 2023 release of OS VectorMap District.

This section describes the three features available in the OS VectorMap District product. The attributes associated with these feature types are listed below along with a brief description of their data properties.

Feature type attribute information

Name and Definition

The name of the attribute and what it is describing.

Data type

The nature of the attribute, for example a numeric value or a code list value.

Size/Length

The length of the attribute provided (optional).

Multiplicity

Describes how many times this element is expected to be populated in the data. An attribute may be optional or mandatory within the product. These are denoted by:

• ‘1’ there must be a value.

• ‘2’ there must be two values.

• ‘n’ there may be one or more values.

• ‘0’ population is optional.

Association

• An association identifies the relationship between features. These relationships are by reference only and the value will be the identifier of the referenced feature.

The product contains twenty one feature types:

• Building

• ElectricityTransmissionLine

• Glasshouse

• RailwayStation

• RailwayTrack

• RailwayTunnel

• MotorwayJunction

• Road

• RoadTunnel

• Roundabout

• Foreshore

• SurfaceWater_Area

• SurfaceWater_Line

• TidalBoundary

• TidalWater

• Woodland

• FunctionalSite

• NamedPlace

• SpotHeight

• AdministrativeBoundary

• Ornament

A building constructed largely of glass for the purposes of commercial horticulture. This is a generalised glasshouse and could be made up of an amalgamation of individual glasshouses. Only glasshouses larger than 5000 m2 are included.

• Belongs to: Buildings and Structures

Glasshouse attributes

Geometry

Polygon representing the generalised glasshouse.

• Type: GM_Surface

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling.

• Type: Integer

• Multiplicity: [1]

Cables used to supply electricity that are suspended between pylons.

• Belongs to: Buildings and Structures

ElectricityTransmissionLine attributes

geometry

Line representing the alignment of the electricity transmission line.

• Type: GM_Curve

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling.

• Type: Integer

• Multiplicity: [1]

A built entity that includes a roof. This is a generalised building and could be made up of an amalgamation of other buildings and structures.

• Belongs to: Buildings and Structures

Building attributes

geometry

Polygon representing the generalised building.

• Type: GM_Surface

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling.

• Type: Integer

• Multiplicity: [1]

Railway tunnels are represented as approximate centrelines of the railway that runs through the tunnel.

• Belongs to: Communications – Rail

RailwayTunnel attributes

Railway tunnels are represented as approximate centrelines of the railway that runs through the tunnel.

geometry

Line representing the alignment of the railway tunnel.

• Type: GM_Curve

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling.

• Type: Integer

• Multiplicity: [1]

Point feature representing the approximate location of numbered junction on a motorway.

• Belongs to: Communications – Road

MotorwayJunction attributes

junctionNumber

The motorway junction number assigned by the Department for Transport.

• Type: CharacterString

• Length: 10

• Multiplicity: [1]

geometry

Point representing the position of the motorway junction.

• Type: GM_Point

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling.

• Type: Integer

• Multiplicity: [1]

The following chapters include information about OS VectorMap District raster, file compression, symbology, georeferencing and formats.

Specification

• Data Source: Derived data

• Number of tiles in Great Britain: 2863 (edgematched)

• Tile size: 10 km x 10 km

Because digital maps frequently cover very large areas they are split down into squares known as tiles, each of which covers part of an overall area.

• Availability: National, country and tile supply available

• Resolution: 254 dots per inch

• Data structure: Raster

• Data Specification: Selection of map features combined

• Colour Palette: 256 fixed colours

• Transfer format: TIFF 8-bit LZW* compressed

• Storage Volume per tile: Compressed: approx. 6.7mb

• Greyscale: A high-quality alternative to colour raster data is to use a GIS to convert data to a greyscale format.

*If LZW compressed formats are used then registration may be required.

OS VectorMap District is supplied in the following raster formats: TIFF 8-bit LZW compressed (6.7 mb)

All railways are represented as lines and are broken where they pass under bridges, buildings or other obstructing detail. Railway sidings and the tracks of travelling structures are not included.

• Belongs to: Communications – Rail

RailwayTrack attributes

classification

The classification of the RailwayTrack. The valid values are defined in the RailwayTrackClassification code list.

• Type: RailwayTrackClassification

• Length: 45

• Multiplicity: [1]

geometry

Line representing the alignment of the railway track.

• Type: GM_Curve

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling. Each classification value has a unique feature code.

• Type: Integer

• Multiplicity: [1]

An inland waterway body sufficiently wide enough to capture as an area feature. Small lakes and small islands in waterbodies are not included.

• Belongs to: Hydrology

SurfaceWater_Area attributes

geometry

Polygon representing the area of surface water.

• Type: GM_Surface

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling.

• Type: Integer

• Multiplicity: [1]

Roundabouts smaller than 450 m2 are represented as point features, and the roads are extended to meet at the centre point. Mini roundabouts are not included.

• Belongs to: Communications – Road

Roundabout attributes

classification

The classification of the roundabout. The valid values are defined in the RoundaboutClassification code list.

• Type: RoundaboutClassification

• Length: 45

• Multiplicity: [1]

geometry

Point representing the position of the roundabout.

• Type: GM_Point

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling. Each classification value has a unique feature code.

• Type: Integer

• Multiplicity: [1]

Road tunnels are represented as approximate centrelines of the road that runs through the tunnel.

• Belongs to: Communications – Road

RoadTunnel attributes

geometry

Line representing the alignment of the road tunnel.

• Type: GM_Curve

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling.

• Type: Integer

• Multiplicity: [1]

Ornament features are facsimiles of artwork, represented as polygons, originally drawn on paper maps to depict coastal rocks, outcropping rocks, boulders, cartographic slopes and scree.

• Belongs to: Land Cover

Ornament attributes

geometry

Polygon representing an individual element of hand-drawn ornament.

• Type: GM_Surface

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling.

• Type: Integer

• Multiplicity: [1]

Polygons defining the extents of tidal water, up to the High Water Mark defined by the TidalBoundaries and the Normal Tidal Limit of rivers. Tidal water is not included under bridges.

• Belongs to: Hydrology

TidalWater attributes

geometry

Polygon representing the area of tidal water.

• Type: GM_Surface

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling.

• Type: Integer

• Multiplicity: [1]

A road is defined as a metalled way for vehicles. A vehicle is defined as one with wheels on both sides of its body. Metalling is defined as any artificial (man-made) surface including areas of asphalt, concrete and gravel. Roads that form part of the public network and driveways to private properties that are over 100 m in length are captured.

Dual carriageways are represented by centrelines when the two carriageways are closer than 32.5 m, roundabouts are represented by points when smaller than 450 m2, dead ends are removed when shorter than 36 m and roads are simplified with a 4 m tolerance.

• Belongs to: Communications – Road

Road attributes

distinctiveName

The name of the road. When a road is dual named, the Welsh or Gaelic name is presented first, followed by a space, a forward slash, a space and then the English name.

• Type: CharacterString

• Length: 100

• Multiplicity: [0..1]

roadNumber

For roads with RoadClassification of Motorway, Primary Road, A Road and B Road, this is the number of the road defined by the Department for Transport.

• Type: CharacterString

• Length: 10

• Multiplicity: [0..1]

classification

The classification of the road. The valid values are defined in the RoadClassification code list.

• Type: RoadClassification

• Length: 45

• Multiplicity: [1]

drawLevel

The drawLevel value of the road, used for cartographic styling. The valid values are defined in the DrawLevelValue code list.

• Type: DrawLevelValue

• Length: 1

• Multiplicity: [1]

override

The override value of the road used for cartographic styling. The valid values are defined in the OverrideValue code list.

• Type: OverrideValue

• Length: 1

• Multiplicity: [1]

geometry

Line representing the alignment of the road.

• Type: GM_Curve

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling. Each classification value has a unique feature code.

• Type: Integer

• Multiplicity: [1]

An inland waterway body not sufficiently wide enough to capture as an area feature.

• Belongs to: Hydrology

SurfaceWater_Line attributes

geometry

Line representing the alignment of the surface water.

• Type: GM_Curve

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling.

• Type: Integer

• Multiplicity: [1]

In England and Wales these tide lines will be the levels of mean tides, for example, of a tide between a spring and neap tide. In Scotland the tide lines are those of mean spring tides. In places where there is no Foreshore (For example, vertical cliffs), the TidalBoundary is classified as 'High Water Mark'.

• Belongs to: Hydrology

TidalBoundary attributes

classification

The classification of the TidalBoundary. The valid values are defined in the TidalBoundaryClassification code list.

• Type: TidalBoundaryClassification

• Length: 45

• Multiplicity: [1]

geometry

Line representing the alignment of the tidal boundary.

• Type: GM_Curve

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling. Each classification value has a unique feature code.

• Type: Integer

• Multiplicity: [1]

OS VectorMap District is a mapping dataset designed for providing contextual mapping output on paper, PCs, handheld devices or the Internet. The vector format of the product consists of layers to enable you to customise and style output to suit your needs.

The product can be used as mapping in its own right or can be used to provide a flexible geographic context reference for customers' overlay information.

The nominal viewing scale is 1:25 000, with a recommended viewing scale range of 1:10 000 to 1:25 000. The data is available on DVD; or download as.zip file

Available Formats

OS VectorMap District will be supplied in three open source formats:

• Vector data in Geography Markup Language (GML) 3.2 Simple Features Profile level 1.

• A national vector dataset in ESRI® Shapefile.

• Specific National Grid Reference square(s) in ESRI Shapefile.

Identifiers

Each feature will be given a unique identifier. The GML product will have the property gml:id which will hold the features unique identifier. The ESRI Shapefile will have the property ID which will hold each features unique identifier. The identifier will not be persistent between product versions and therefore there will be no change history information for a feature.

UML Diagram and Table Conventions

The data structure is described below by means of UML class diagrams and accompanying tables containing text. The UML diagrams conform to the approach specified in ISO 19103 Conceptual schema.

Colour conventions have been used in the diagrams and tables to distinguish the properties that have been added in this specification.

In the UML diagram classes in the Ordnance Survey product specification are orange. All code lists are coloured blue. The tables which follow in this Technical Specification use orange for a feature type and blue for a code list.

Lexical Conventions

• Class names are conceptually meaningful names (singular noun) in UpperCamelCase

• Class names end in “Value” or “Classification” where the class is assigned the stereotype <<CodeList>>

• Property names (attributes and associations) are in lowerCamelCase

Stereotypes

The following stereotypes are used on UML elements:

Index

• GML Overview

• Raster specification

• Georeferencing

• Feature types

• Code lists

• Attributes

• Feature codes

• Styling of Land and Sea

Supply Format

OS VectorMap District is available as:

• Vector: ESRI Shapefile with each tile dataset zipped using gzip.

• Raster: TIFF and compressed using LZW (Lemple-Ziv-Welch) compression.

• Data: GML v3.2. Simple Features and schema zipped as a single file using gzip.

Supply Media

OS VectorMap District can be ordered from the Ordnance Survey OS OpenData™ website. This allows you to order your area of choice and format.

Data is available on DVD or as a download from: os.uk/oswebsite/products/vectormap/district/index.html

The National Grid coverage for OS VectorMap District

Ordnance Survey divides Great Britain into squares 100 km by 100 km. Each of these squares has a unique two-letter reference, for example, TG in the diagram below.

OS VectorMap District vector format tiles are identified by quoting the National Grid reference of the south-west corner of the 100 km² area they cover, for example TG.

To describe an OS VectorMap District raster format tile, which covers 10 km by 10 km, first add a two-digit reference to the 100 km by 100 km square reference, with the easting first followed by the northing, for example, TG23. For additional information on how to use the National Grid, visit the Ordnance Survey website at: os.uk/support/the-national-grid.html

Coverage and File Size

• Coverage is England, Wales and Scotland.

Shapefile:

• 55 tiles, each covering 100 km x 100 km comprise the national set.

• Each tile comprises a set of up to 24 Shapefiles.

• Each Shapefile holds a single feature type.

• Features within each Shapefile are cut into a 10 km x 10 km grid.

• Tile sizes range from 1 Mb to 697 zipped Mb.

• The data is not encrypted.

GML data:

• 55 tiles, each covering 100 km x 100 km comprise the national set.

• Each 100 km tile is split into 20 km by 20 km tiles (809 in total).

• Each tile comprises of up to 57 Feature Codes.

• Features that cross the grid line are split.

• Tile sizes range from 1 Mb to 347 Mb.

• The data is not encrypted.

TIFF:

• 2863 tiles, each covering 10 km x 10 km comprise the national set.

• Tiles range from 2 Mb to 6.7 Mb.

Seamless data

In the vector product features that cross tile edges are included in both tiles, represented as hairy tiles. This avoids the creation of invalid geometries by arbitrary cutting, and facilitates greater use of the data in analytical applications. All features have unique identifiers which can be used to remove duplicates across tile edges, if required.

Note that these identifiers will not be persisted or maintained between product releases.

It is the flexibility to select and style the different feature classes in different ways that makes the vector format of OS VectorMap District such a versatile contextual mapping product. It can be flexibly styled in a wide variety of ways to best provide a geographic context to the customer’s overlay information.

The raster version is ready-styled as backdrop and full colour and these styles are fixed within the limitations of the image viewing software. Below is an example of both the raster styles. The full graphic legends are available online here.

This release note provides information relating to the May 2023 release of OS VectorMap District.

Feature counts

Product issues and enhancements

GeoPackage format changes

We've updated some of our products available in GeoPackage format to align with Open Geospatial Consortium (OGC) standards and we've also fixed various formatting inconsistencies. Full details of these changes for OS VectorMap District can be found in the following sub-sections.

Attribute names

The following attribute names have changed from camel case to snake case:

Layer names

The following layer names have changed from title case to snake case:

• AdministrativeBoundary to administrative_boundary

• Building to building

• ElectricityTransmissionLine to electricity_transmission_line

• Foreshore to foreshore

• FunctionalSite to functional_site

• Glasshouse to glasshouse

• MotorwayJunction to motorway_junction

• NamedPlace to named_place

• RailwayStation to railway_station

• RailwayTrack to railway_track

• RailwayTunnel to railway_tunnel

• Road to road

• RoadTunnel to road_tunnel

• Roundabout to roundabout

• SpotHeight to spot_height

• SurfaceWater_Area to surface_water_area

• SurfaceWater_Line to surface_water_line

• TidalBoundary to tidal_boundary

• TidalWater to tidal_water

• Woodland to woodland

Column name

The geom column name has been changed to geometry.

Attribute order

The attributes in the following feature type layers have changed order:

Functional Site

Motorway Junction

Named Place

Railway Station

Road

Spot Height

Next release

The next release of OS VectorMap District is scheduled for November 2023.

OS VectorMap District is a free mapping dataset designed for providing contextual mapping output on paper, PCs, hand-held devices, or the Internet. Available as pre-styled static images (Raster data) and points, lines, and polygons (Vector data). The vector format of the product consists of layers to enable you to customise and style output to suit your needs.

OS VectorMap District has been improved to offer enhanced functionality as well as offering greater consistency with other OS products, including OS Open Map – Local.

The product now offers significantly improved generalisation, resulting in a more attractive map that compliments the more detailed street-level OS VectorMap® Local product.

Key Features

The key features of OS VectorMap District product are:

• Provides a clear visual backdrop map that can be easily styled to meet specific needs.

• Please refer to the Product Cartographic Stylesheets webpage for styling options: os.uk/resources/carto-design/cartographic-stylesheets.html

• Offers flexibility to user through ease of use to control content display.

• Suitable for varying scenarios around the mid-range scale of 1:25 000

• Analyse data in relation to important public buildings, roads, railways, lines and more

• Compatible with other open datasets available from data.gov.uk and many other sources.

Applications

The purpose of OS VectorMap District data is to support a wide range of customer applications that utilise geographic information. These may include:

• Backdrop mapping on your website

For your area, you may wish to take advantage of free data on the Government’s data.gov.uk website, for example, air pollution data. The layered structure of OS VectorMap District enables you to display the map to show only the features you want to show – for example, roads, place names and buildings.

You may want to style the data as a faded map backdrop to ensure your own or third-party overlaid data are clearly portrayed. For example, backdrop mapping can be used by public sector organisations to share information with the public. Such applications include providing the location of GP surgeries or dentists to the public, or the performance of schools based on exam results in a district.

• Develop an interactive web application

OS VectorMap District has been designed for on-screen use, with generalised detail and an appropriate level of content that gives an uncluttered appearance. Subscribers to the OS OpenSpace® application programming interface (API) can build location-based services using the map to guide smartphone users and provide location-specific information.

• Display your business location

Do you want to tell your customers how to get to your business? The district view of OS VectorMap District is ideal for creating a map of a suburban area or part of a city, complete with locality names for context.

Your customers can then zoom in to your business at a street level using the OS VectorMap District product.

OS VectorMap District topographic features are generalised representations of real-world objects, including buildings, roads, railways, and rivers. The data also includes non-topographic features such as administrative and electoral boundaries (GML and Shapefile format only), cartographic text and symbols.

Generalisation

The detail within OS VectorMap District has been generalised from Ordnance Survey large-scale data. Map generalisation is the process of reducing the scale and complexity of map detail whilst maintaining the important elements and characteristics of the location.

Map generalisation comprises of the following processes:

• Selection/omission: some features that appear at larger scales are not selected at the smaller scales. For example, in the public amenities layer individual features in close proximity can be grouped to a single point.

• Simplification: simplification can take a number of forms in OS VectorMap District. It can be line simplification, for example, in a vector product; a very winding stream could have the number of data points that represent it reduced.

• Exaggeration: features that are small but are too important to a particular landscape to be omitted are enlarged. For example, some isolated rural buildings are often enlarged to a minimum size rather than being omitted.

• Aggregation: aggregation is the combining of a number of small features to make a larger one, such as buildings.

• Symbolisation: features that are shown in detail in other OS products, such as OS VectorMap Local may be shown by standard symbolisation in OS VectorMap District. For example, railway stations are depicted as point symbols.

• Displacement: the movement of the representation of a feature away from its ground position in order to maintain its prominence. There is very little displacement in OS VectorMap District, but in certain circumstances, some features may be moved away from adjacent detail if their representation would otherwise be lost; for example, some buildings are moved away from road edges to ensure they remain prominent.

A definition for registering raster images within a geographic framework is the process of assigning map coordinates to the raster image data and re-sampling the pixels of the image to conform to the map projection grid. This allows tiles of map data to be located in their correct geographic position relative to the map projection and also to themselves.

Great Britain is surveyed and mapped using the Transverse Mercator (or Gauss-Kruger) projection, so all raster tiles will be mapped to this projection as it applies to Ordnance Survey National Grid if using World or TAB files supplied by Ordnance Survey.

Within the MIF record header the following information will be found under COORDSYS:

CoordSys Earth Projection 8, 79, "m", -2, 49, 0.9996012717, 400000, -100000 Bounds (4.17232513428e-011, 7.7486038208e-011) (700000, 1300000)

This information relates to the Transverse Mercator projection, its position relative to the rest of the world and also an individual tile’s position relative to the projection. The record header is constructed as (not all fields have to be used):

CoordSys Earth Projection 8 The 8 relates to a MapInfo identifier, in this case the Transverse Mercator projection.

79 a MapInfo identifier, in this case this relates to Ordnance Survey of Great Britain 1936, Airy ellipsoid.

“m” relates to the unit of measurement, in this case metres.

-2 this is the origin of the projection in respect of longitude.

49 this is the origin of the projection in respect of latitude.

0.9996012717 indicates the distortion of the tile at the central meridian. A value of 1.0 would indicate no distortion at all. However, distortion within this projection is minimal even at the far western or eastern limits.

400000, -100000 these figures indicate the false origin of the British National Grid.

They represent the south-west corner of the Transverse Mercator projection, which overlays Great Britain, so all coordinates for any tile, no matter what scale, will always be positive.

Bounds: (4.17232513428e-011, 7.7486038208e-011) these values represent the minimum bounding X and Y coordinates for the tile. (700000, 1300000) these values represent the maximum bounding X and Y coordinates for the tile.

Legends Backdrop and Full Colour

Both Legends can be found on the website and downloaded

OS VectorMap District is a simple vector dataset with a nominal scale of 1:25 000 covering the whole of Great Britain that has been designed for creating graphical mapping. The product can be used as mapping in its own right or can be used to provide a flexible geographic context reference for customers’ overlay information.

How to get this product

The part of the shore or beach which lies between the Low Water Mark and High Water Mark defined by the TidalBoundaries. The same condition may exist in non-contiguous off-shore areas.

• Belongs to: Hydrology

Foreshore attributes

geometry

Polygon representing the area of foreshore.

• Type: GM_Surface

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling.

• Type: Integer

• Multiplicity: [1]

A line feature representing the limit of a government administrative area. In the event that a boundary represents the limit of more than one administrative area, classifications are applied in hierarchical order, with priority given to the largest containing area. An exception is made for National boundaries, which will be coincident with the underlying local government boundary.

• Belongs to: Administrative Boundaries

AdministrativeBoundary attributes

classification

The classification of the AdministrativeBoundary. The valid values are defined in the AdministrativeBoundaryClassification code list.

• Type: AdministrativeBoundaryClassification

• Length: 45

• Multiplicity: [1]

geometry

Represents the limit of a government administrative area.

• Type: GM_Curve

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling. Each classification value has a unique feature code.

• Type: Integer

• Multiplicity: [1]

A representative point feature giving the general location of a settlement name or geographic place name, for the purposes of text placement.

• Belongs to: Named Places

NamedPlace attributes

distinctiveName

The settlement name or geographic place name. When a place is dual named, the Welsh or Gaelic name is presented first, followed by a space, a forward slash, a space and then the English name.

• Type: CharacterString

• Length: 100

• Multiplicity: [1]

classification

The classification of the NamedPlace. The valid values are defined in the NamedPlaceClassification code list.

• Type: NamedPlaceClassification

• Length: 40

• Multiplicity: [1]

fontHeight

A suggested text size to use for placing the distinctiveName as cartographic text. For most names the text size is proportional to the size of the area to which the name applies. For valleys the text size is based on the valley length and for hills/mountains, the text size is based on the height of the summit. The valid values are defined in the FontHeightClassification code list.

• Type: FontHeightClassification

• Length: 11

• Multiplicity: [1]

textOrientation

Suggested text orientation (in degrees) to use for cartographic text placement of valley names, names of stretches of water and estuaries.

• Type: Measure

• Multiplicity: [1]

geometry

Point representing the cartographic position of the named place.

• Type: GM_Point

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling. Each classification value has a unique feature code.

• Type: Integer

• Multiplicity: [1]

Areas of trees; coniferous, non-coniferous and mixed are represented as polygons. Small areas of woodland are omitted and small clearings in woodland are filled.

• Belongs to: Land Cover

Woodland attributes

geometry

Polygon representing the area of woodland.

• Type: GM_Surface

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling.

• Type: Integer

• Multiplicity: [1]

Point feature which in most cases represents the location of a summit of a hill or mountain, together with an elevation measurement.

• Belongs to: Height

SpotHeight attributes

Height

The elevation of the point above datum, rounded to the nearest metre.

• Type: Measure

• Multiplicity: [1]

geometry

In most cases the location of a summit of a hill or mountain, rounded to the nearest metre.

• Type: GM_Point

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling.

• Type: Integer

• Multiplicity: [1]

A point feature that represents the location of certain types of function or activity with appropriate attribution.

• Belongs to: Land Use

FunctionalSite attributes

distinctiveName

The name of the site (for example, ‘Brighton College’). Note this may be null if the captured value is a house number.

• Type: CharacterString

• Length: 150

• Multiplicity: [0..1]

classification

A description of the actual function of a site (that is, airfield, junior school, hospital and so on.) The valid values are defined in the FunctionalSiteClassification code list.

• Type: FunctionalSiteClassification

• Length: 65

• Multiplicity: [1]

geometry

A representative point giving the general location of the functional site, for the purposes of text placement.

• Type: GM_Point

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling. Each classification value has a unique feature code.

• Type: Integer

• Multiplicity: [1]

A code list or enumeration is a controlled set of values which can be used to populate a specific column.

Code List: RailwayStationClassification

Code List: TidalBoundaryClassification

Code List: RoundaboutClassification

Code List: OverrideValue

Code List: DrawLevelValue

Code List: NamedPlaceClassification

Code List: RailwayTrackClassification

Code List: FunctionalSiteClassification

Code List: RoadClassification

Code List: FontHeightClassification

Styling of Land and Sea in Ordnance Survey Mapping Products

This section details an alternative approach for applying a background colour to areas of the map that are not covered by Tidal Water. The solution requires an ESRI shape file defining the spatial extents of each product to be provided as a download on the Ordnance Survey website as found here:

These polygons are then styled in a GIS with the required colour for land:

OS VectorMap District polygons for TidalWater can then be overlaid on top. This ensures that the background land colour is only visible for areas of land:

Most GIS allow a background colour to be applied to the entire display window. In ArcMap this is achieved by right- clicking in the data frame, selecting Data Frame Properties, selecting the Frame tab and setting a background colour. The background colour should be set to be the same colour as TidalWater:

Polygons defining areas of land for the whole world can be downloaded from here: (click on ‘Download land’)

This data is defined in the WGS84 coordinate system. Some GIS will transform this on-the-fly to British National Grid, for others it may be necessary to apply a coordinate transformation first. This data can be added to the map below the two existing layers (ProductExtents and TidalWater). This ensures that only the additional land masses beyond the areas maintained by Ordnance Survey are visible:

This is a simple user guide for those with no previous knowledge of geographic information systems (GIS).

This guide will introduce users to downloading OS OpenData™, creating simple maps with Quantum GIS (QGIS), and exporting the map as a PDF or JPEG file.

The aim of this exercise is to produce a map of Southampton at a scale of 1:20 000.

OS VectorMap® District (Vector) format is updated twice a year and is appropriate for maps of scale 1:15 000-1:30 000. If a greater level of detail is required we recommend OS VectorMap Local.

For more information on OS VectorMap District go to:

www.os.uk/business-and-government/products/vectormap-district.html

The topics covered in this guide include:

• Downloading OS OpenData

• Opening OS OpenData in QGIS

• Styling vector data

• Opening and saving maps in Composer

OS VectorMap District - XML schema

XML schema for OS VectorMap District is available as a link from the product page here.

OS VectorMap District - Full colour legend

A full-style colour legend for OS VectorMap District is available as a PDF download from the product page here.

OS VectorMap District - Backdrop legend

A backdrop-style legend for OS VectorMap District is available as a PDF download from the product page here.

• Firstly OS VectorMap District (Vector) format needs to be downloaded from the OS site: www.os.uk/opendatadownload/products.html

• Scroll to OS VectorMap District, ensure that the data type is Vector. Select grid reference square using the two letter reference list. Southampton lies in the SU grid reference square, so SU has been selected from the reference list.

Here is a larger image of the National Grid Reference squares:

• Tick the box for Download (as seen in download page image). Scroll down to the bottom of the page and click Next.

• Fill in the details required and you will receive an email with a link to download the data as a .zip file. Save to a designated folder. Once the download is complete, extract the file.

Now you should have a data folder with the all the components as SHX, SHP, PRJ and DRB files.

• As the download doesn’t come with Styled Layer Descriptors (SLDs), these need to be downloaded from the GitHub: https://github.com/OrdnanceSurvey/OS-VectorMap-District-stylesheets

On the webpage click ‘Download ZIP’.

• Save the file. Once downloaded, extract the file and this will create a folder which contains both ESRI Shapefile stylesheets and GML stylesheets. Later we will be using the ESRI Shapefile stylesheets.

• Once you are happy with the scale and position, click Project > New Print Composer.
• A window will open asking for an ID/Title, however it is not required. Click OK.
• A new window will open showing a blank page. To insert the map from QGIS click on ‘Add new map’ (see below).

Left click and then drag a rectangle to select the dimension of the added map. Once added the position of the map within the frame can be adjusted by selecting ‘Move item content’ (see above).

• Click on ‘Item Properties’ on the task bar on the right. The specific scale can be selected here, and if you scroll down there are several other options including ‘Position and Size’. Here the dimensions of the map on the page can be adjusted in millimetres. Careful, as when altering the position and size the scale will also change.
• Once you are happy with the image you can export the map as an image or a PDF by selecting ‘Export as image’ or ‘Export as PDF’ respectively (see below). And save within an appropriate folder.

• Your final JPEG image should looks similar to this:

Code List: AdministrativeBoundaryClassification

1. Open QGIS from Start > All Programs > QGIS Brighton > QGIS Desktop 2.6.1

2. To add the OS VectorMap. Select ‘Add vector layer’ from the application toolbar

3. Click ‘Browse’ and navigate to the data folder OSVectorMapDistrict (ESRI Shape File)SU > data.

4. Click on the drop down menu next to File name and select ESRI shapefiles (*.shp, *.SHP).

5. Select all the shape files and click ‘Open’. Now you should have a map that looks similar to this:

• Once open you can move about and investigate the map using some of these tools:

Pan tool Zoom in/Zoom out

1. To restore the image to its original view, right click on one of the vector layers and click ‘Zoom to layer’.

• For each layer the colours have been assigned randomly. To make the map legible the Styled Layer Descriptors can be applied to each layer.

To do this first right click on the ‘SU_Woodland’ layer and select ‘Properties’.

• This will open a new window. Make sure the ‘Style’ tab on the left is selected.

• Click ‘Load Style’ and a new window will open, navigate to the downloaded stylesheet folders

OS-VectorMap-District-stylesheets-master > ESRI Shapefile stylesheets > QGIS stylesheets (QML) > Full Colour style and select the Woodland QML file and click ‘Open’.

• Repeat this for each layer selecting the respective QML file for each layer.

• For maximum legibility rearrange the order of the layers to match the image below:

• By clicking on the box next to the layer name the layer can be included or removed from the map.

• The resultant map should look similar to this:

• The map is most functional for scales 1:15 000-1:30 000. For this tutorial we want a map of an area of Southampton at a scale of 1:20 000. Use the ‘Pan tool’, ‘Zoom in’ and ‘Zoom out’ to position the map over Southampton at an appropriate scale, or alternatively set the scale of the map by typing in the scale bar, which is at the bottom of the screen.

• The map should now look similar to this:

• Once you are happy with the scale and position, click Project> New Print Composer.

• A window will open asking for an ID/Title, however it is not required. Click OK.

• A new window will open showing a blank page. To insert the map from QGIS click on ‘Add new map’ (see below).

Left click and then drag a rectangle to select the dimension of the added map. Once added the position of the map within the frame can be adjusted by selecting ‘Move item content’ (see below).

• Click Item Properties on the task bar on the right. The specific scale can be selected here, and if you scroll down there are several other options including Position and Size. Here the dimensions of the map can be adjusted in millimetres.

Careful, as when altering the position and size the scale will also change.

• Once you are happy with the image you can export the map as an image or a PDF by selecting

‘Export as image’ or ‘Export as PDF’ respectively (see below). And save within an appropriate folder.

• Your final JPEG image should looks similar to this:

This is a simple guide for those with no previous knowledge of geographic information systems (GIS). This guide will introduce users to downloading OS OpenData™, creating simple maps with Quantum GIS (QGIS), and exporting map images as a PDF or JPEG file.

The aim of this exercise is to produce a map of Southampton at a scale of 1:17 000.

OS VectorMap® District (Raster) format is updated twice a year and is appropriate for maps of scale 1:15 000-1:30 000. If a greater level of detail is required we recommend OS VectorMap Local.

For more information on OS VectorMap District (Raster) format go to:

The topics covered in this guide include:

Feature Codes represented in the vector product

Point feature representing the buildings and platforms by a railway line where a train may stop to pick-up or drop-off goods or passengers.

• Belongs to: Buildings and Structures

RailwayStation attributes

distinctiveName

The name of the station, consistent with the names used by National Rail Enquiries. The suffix ‘Station’ is not added to the name.

• Type: CharacterString

• Length: 150

• Multiplicity: [1]

classification

The classification of the RailwayStation. The valid values are defined in the RailwayStationClassification code list.

• Type: RailwayStationClassification

• Length: 65

• Multiplicity: [1]

Geometry

Point representing the position of the railway station.

• Type: GM_Point

• Multiplicity: [1]

featureCode

A unique feature code to facilitate styling. Each classification value has a unique feature code.

• Type: Integer

• Multiplicity: [1]

• Open QGIS from Start>All Programs>QGIS Brighton>QGIS Desktop 2.6.1

• To open the OS VectorMap District (Raster) format Select ‘Add raster layer’ (see below)