# OS MasterMap Sites Layer Getting Started Guide

This getting started guide shows you how to load the GML supply of the OS MasterMap Sites Layer into several commonly used geographical information system (GIS) applications.

## Product supply and formats <a href="#id-1.1-product-supply-and-formats" id="id-1.1-product-supply-and-formats"></a>

OS MasterMap Sites Layer is supplied as an online download in the [OS Data Hub](https://osdatahub.os.uk/).

You can order OS MasterMap Sites Layer data for either all of Great Britain or by 5 km² tile. In the 5 km² tiles, features are not clipped at tile edges, resulting in what is known as 'hairy' tiles.

The product is available in the following formats:

* GeoPackage
* Vector tiles (MBTiles)
* GML (3.2.1)

All formats contain three layers: Functional Site, Access Point, and Routing Point.

## File naming conventions <a href="#id-1.2-file-naming-conventions" id="id-1.2-file-naming-conventions"></a>

The GML file naming conventions for OS MasterMap Sites Layer are:

#### National sets

National datasets are grouped into the seven themes within Sites Layer: air transport, education, medical care, rail transport, road transport, water transport, and utility and industrial.

File names follow this pattern: <*product>\_\<theme>\_\<area>*.gz, for example, *osmmsites\_airt\_england.gz*.

#### Tiled data

Tiled datasets are provided in 5 km² tiles. Each tile includes all themes present in that tile. Files names follow this pattern: <*5k tile ID>*.gz, for example, *HP5000.gz*.

## Using GeoPackage and vector tile formats <a href="#id-1.3-using-geopackage-and-vector-tile-for" id="id-1.3-using-geopackage-and-vector-tile-for"></a>

Guidance on how to use this product in GeoPackage and vector tiles formats can be found in the following documents:

* [*Getting Started with GeoPackage*](/os-downloads/resources/product-resources/getting-started-with-geopackage-and-vector-tiles-guides/getting-started-with-geopackage.md)
* [*Getting Started with Vector Tiles*](/os-downloads/resources/product-resources/getting-started-with-geopackage-and-vector-tiles-guides/getting-started-with-vector-tiles.md)


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