🆕Comparison of OS MasterMap Greenspace Layer and OS NGD

Comparing OS MasterMap Greenspace Layer to corresponding feature types in the OS NGD.

The OS MasterMap Greenspace Layer product will become End of Life on 31 March 2027. As of this date, Ordnance Survey will cease to maintain or publish updates, and access to the product will be removed from the OS Data Hub, OS Features API and OS Vector Tile API.

For the latest updates and information on this and other products, please refer to our strategic product roadmap and End of Life Product Notice pages.

Overview

The purpose of this page is to provide a technical summary of things to consider when migrating from OS MasterMap Greenspace Layer to the corresponding four feature types (Land, Rail, Road Track Or Path, and Water) within the OS National Geographic Database (OS NGD). The information currently provided in OS MasterMap Greenspace Layer is contained within the following OS NGD collections: the OS Land Features, OS Transport Features and OS Water Features Collections.

This page covers data supply and formats, as well as a comparison of the attribution of the two products.

Key features

The OS MasterMap Greenspace Layer product includes the following key attribution:

• Primary Form and Secondary Form – describing land cover

• Primary Function and Secondary Function – describing land use

OS NGD data offers the following improvements:

• Full coverage of Great Britain, as opposed to coverage being limited to urban areas only for OS MasterMap Greenspace Layer; the coverage comparison maps further down the page give a good visual representation of greenspace data coverage differences between the products.

• Land cover (Primary and Secondary Form are the equivalents in OS MasterMap Greenspace Layer) is presented as a hierarchy with more than 100 values, compared to 6 values in OS MasterMap Greenspace Layer.

• Land use (Primary and Secondary Function are the equivalents in OS MasterMap Greenspace Layer) is presented as a hierarchy with more than 50 values, compared to 18 values in OS MasterMap Greenspace Layer.

• Alternative land cover and land use classifications are available in the OS NGD:

  • Land cover

    • European Nature Information System (EUNIS) classification scheme

    • UK Biodiversity Action Plan (BAP) Broad Habitats classification scheme

  • Land use

    • National Land Use Database (NLUD)

    • Address (BS7666)

• Data in the three OS NGD collections is updated up-to-daily (updates are 6-monthly for OS MasterMap Greenspace Layer).

• Every area feature in the OS NGD has a code assigned that indicates the local authority it lies within – Government Statistical Service (GSS) codes – allowing summaries of land use and land cover.

• Richer change metadata at attribute level is available in the OS NGD to improve the analysis of change over time.

• The three OS NGD collections contain a link to the Site Feature Type in the OS Land Use Features Collection, allowing features to be grouped where they lie within a common occupied extent, such as a park or residential property.

OS NGD greenspace recipe guide now available

There's no like-for-like replacement download product for OS MasterMap Greenspace Layer, but you can create a recipe in OS Select+Build to download the equivalent greenspace data from the OS NGD.

The greenspace recipe guide is available on the OS NGD documentation site; it provides detailed step-by-step instructions outlining how you can combine and filter the four OS NGD feature types to create a greenspace recipe.

You can adapt the suggested greenspace recipe at the recipe creation or editing stage so that it fully meets your needs.

Feature types

OS MasterMap Greenspace Layer has one feature type:

• Greenspace Area

In the OS NGD, there are four corresponding feature types:

• Land (in the OS Land Features Collection)

• Rail (in the OS Transport Features Collection)

• Road Track Or Path (in the OS Transport Features Collection)

• Water (in the OS Water Features Collection)

Comparison maps

Coverage comparison maps

Below are two maps showing the greenspace coverage for Great Britain provided by OS MasterMap Greenspace Layer and by OS NGD data using the greenspace recipe:

Maps comparing the greenspace coverage of Great Britain provided by OS MasterMap Greenspace Layer vs. OS NGD data.

Attribution comparison maps

Below is a pair of interactive maps over Exeter showing the similarities between the OS MasterMap Greenspace Layer (top) and the OS NGD feature types (bottom); clicking on a feature in either map will open a pop-up displaying the shared attributes:

Currency

OS MasterMap Greenspace Layer has an update frequency of six monthly (April and October), whereas the OS NGD has an update frequency of up-to-daily for the three collections.

Data supply

File formats

OS MasterMap Greenspace Layer is available in:

• ESRI Shapefile

• GML

• GeoPackage

• Vector tiles

It is also currently supplied in the OS Features API and the OS Vector Tile API (although access to the product will be removed from both APIs in March 2027).

The OS Land Features, OS Transport Features and OS Water Features Collections of the OS NGD are available in:

• GeoPackage

• CSV (comma-separated values)

• GeoJSON

• Vector tiles

The download service of OS Select+Build supplies GeoPackage and CSV formats, while OS NGD API – Features supplies GeoJSON, and OS NGD API – Tiles supplies vector tiles.

The OS NGD Documentation site contains further guidance on the differing formats and APIs available:

• OS NGD file formats and naming

• Getting Started with OS NGD API – Features

• Getting Started with OS NGD API – Tiles

Data ordering

Through the OS Data Hub, it's currently possible to order OS MasterMap Greenspace Layer for all of Great Britain or a customisable area (5km² tiles) in the following formats:

• Geography Markup Language (GML)

• ESRI Shapefile

• GeoPackage

• Vector tiles

All OS NGD download data is supplied through OS Select+Build in the OS Data Hub. OS Select+Build offers a much more tailored experience to ordering and downloading OS data, with an improved range of options, including:

• True areas of interest are supplied, as opposed to 5km² tiles, removing need to deduplicate adjoining 'hairy' tiles.

• In addition to updates being delivered as full refreshes, it is also possible to take Change-Only Updates (COUs) in CSV format for full Great Britain coverage, so you'll receive only the updated features.

With OS Select+Build, it is also possible to filter your supply so you receive only the features that you require. For example, OS Land Cover Tier A and OS Land Use Tier A.

The OS NGD Documentation site contains guidance on downloading with OS Select+Build and using and loading OS NGD data in both CSV and GeoPackage formats:

• The greenspace recipe guide provides detailed step-by-step instructions outlining how you can combine and filter the four OS NGD feature types to create a greenspace recipe in OS Select+Build.

• Downloading with OS Select+Build

• Getting Started with CSV

• Getting Started with GeoPackage

Unique identifiers

In OS MasterMap Greenspace Layer, persistent managed identifiers are supplied called TOIDs (Topographic Identifiers). TOIDs are strings of up to 20 characters, starting with 'osgb'; the remaining characters are digits (0 to 9). As OS MasterMap Greenspace Layer contains a subset of features from OS MasterMap Topography Layer, the TOIDs provided in OS MasterMap Greenspace Layer are the same identifiers as for the corresponding features in OS MasterMap Topography Layer.

The OS NGD uses a new identifier called the OSID (OS Identifier) to uniquely identify features. The OSID is a Globally Unique Identifier (GUID) and requires no centralised authority to ensure uniqueness.

The Land, Rail, Road Track Or Path, and Water Feature Types in the OS NGD contain a TOID attribute, which allows linking back to OS MasterMap Greenspace Layer.

Attribution comparison

OS NGD data contains richer information on land use and land cover, and is structured to be simple to navigate and query.

The attribution comparison maps further up the page show the similarities between OS MasterMap Greenspace Layer data and the four OS NGD feature types, and the extra attribution available through the latter.

The table below compares the attribution available for the two products:

OS MasterMap Greenspace Layer Attribute	Purpose	OS NGD Attribute	Purpose
toid	The unique reference number of the feature in OS MasterMap Topography Layer.	toid	The TOID is provided in the OS NGD to enable migration. The OSID is the primary identifier for the OS NGD.
version	The version number of the feature in OS MasterMap Topography Layer. This identifies the specific version of Topography Layer feature this dataset was created from.	versiondate, versionavailablefromdate, versionavailabletodate	Date on which the version was last updated; the date on which this version of the feature became the latest version; the date on which this version of the feature was superseded by an update or ceased to exist.
primaryFunction	The main function of the greenspace area.	oslandusetiera, oslandusetierb	Classifications of land use provided at a high level (Tier A) and in more detail (Tier B).
secondaryFunction	Where a polygon has more than one greenspace function present, this field will be populated with the second function.	oslandusetiera, oslandusetierb	Classifications of land use provided at a high level (Tier A) and in more detail (Tier B).
primaryForm	The main form of the greenspace area.	oslandcovertiera, oslandcovertierb	Classifications of land cover provided at a high level (Tier A) and in more detail (Tier B).
secondaryForm	Where a polygon has more than one greenspace form present, this field will be populated with the second form.	oslandcovertiera, oslandcovertierb	Classifications of land cover provided at a high level (Tier A) and in more detail (Tier B).

All the OS MasterMap Greenspace Layer attributes above use the names from the GML format; please see the Attribute mapping page for the ESRI Shapefile, GeoPackage and vector tiles equivalents.

Additional attribution available for OS NGD data

The OS NGD also provides additional information beneficial to greenspace use cases:

OS NGD Information	Attribute	Purpose
Description	description	A single descriptive value intended for a quick understanding of what the feature represents.
Change metadata	firstdigitalcapturedate, changetype, geometry_evidencedate, geometry_updatedate, geometry_source, geometry_capturemethod	Information explaining data changes.
Link to Sites	smallestsite_siteid, smallestsite_landusetiera, smallestsite_landusetierb, largestsite_landusetiera, largestsite_landusetierb	References to OS NGD Land Use Theme data for more land use information.
NLUD classification	nlud_code, nlud_orderdescription, nlud_groupdescription	An alternative land use classification that uses a code defined in the NLUD schema.
Address classification	address_classificationcode, address_primarydescription, address_secondarydescription	An alternative land use classification that uses a code defined in the Address / BS7666 schema.
GSS code	lowertierlocalauthority_gsscode, lowertierlocalauthority_count	The unique identifier of the Lower Tier Local Authority administrative area provided by the Office for National Statistics that the feature lies within.
Habitat information	scheme, habitatcode, habitatdescription, percentage	Habitat classifications for natural topographic features mapped to the EUNIS and UK BAP classification schemes.

Help and support

Supporting links

The OS NGD Documentation site has further information that you may find useful. Some particularly relevant sections that may aid you with migration are:

• Greenspace recipe guide

• OS NGD Fundamentals

• OS Land Features Collection

• OS Transport Features Collection

• OS Water Features Collection

Contact us

If you have any questions, need assistance, or want to provide feedback, please don't hesitate to reach out to us at os.uk/contact-us.