> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-downloads/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/os-downloads/products/transport-network-portfolio/os-open-usrn/os-open-usrn-overview/product-supply.md).

# Product supply

## Available format <a href="#bookmark18" id="bookmark18"></a>

This product is only available in GeoPackage format. It is supplied as a single GeoPackage for the whole of Great Britain.

### GeoPackage overview

GeoPackage (GPKG) is an open standard data format as defined by the Open Geospatial Consortium (OGC). GeoPackage 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.

Please be advised that older versions of GIS software may need updating before being able to display and interact with GeoPackage files.

GeoPackage offers users the following benefits:

* The single file is easy to transfer and offers the end-user a rich experience.
* Attribute names are not limited in length, making it user-friendly.
* The file size limit is very large at 140TB, 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 [‘Getting Started with GeoPackage’ guide](/os-downloads/resources/product-resources/getting-started-with-geopackage-and-vector-tiles-guides/getting-started-with-geopackage.md). Further detailed information on GeoPackage can be taken from the [GeoPackage website](https://www.geopackage.org).

## Supply mechanism

OS Open USRN is supplied as a free online download and is available without registration from the [OS Data Hub](https://osdatahub.os.uk/data/downloads/open).

## Coverage

This product covers Great Britain and includes all USRNs which are present in [OS MasterMap Highways Network](/os-downloads/products/transport-network-portfolio/os-mastermap-highways-network-fundamentals.md).

OS Open USRN is available as a **Full Supply only**. Areas of interest (AOI) orders and Change-Only Updates (COUs) are not available for this product.

## Currency

The product will be refreshed on a monthly basis (in-line with the OS MasterMap Highways Network product release on the first working day of each month).


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