> 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/~/changes/AJZwzCsyrD9hiTbOxIbO/networks/os-mastermap-highways-network-core-principles/os-mastermap-highways-network-getting-started-guide/coverage.md).

# Coverage

The products cover Great Britain. Information from the National Street Gazetteer will only be provided for England and Wales. Information from the Scottish Street Gazetteer will only be provided for Scotland.

## Non-geographic chunks <a href="#bookmark13" id="bookmark13"></a>

OS MasterMap Highways Network products will only be supplied as non-geographic chunks. Non- geographic chunking is a way of dividing up data into chunks that are supplied in separate volumes that have a feature count, as opposed to a given geographic National Grid area. For this reason, it is possible for features from various geographic locations to appear in one volume and for adjacent features to appear in different volumes.

Non-geographic chunk volumes are designed to be loaded into spatial databases but can be used in a file format, provided all chunks are translated or imported into the system at the same time. For information on the volume feature counts for each feature type in OS MasterMap Highways Network, please see the [volume feature count page](/os-downloads/~/changes/AJZwzCsyrD9hiTbOxIbO/networks/os-mastermap-highways-network-core-principles/os-mastermap-highways-network-overview/volume-feature-count.md) in the [OS MasterMap Highways Network Product Guide](/os-downloads/~/changes/AJZwzCsyrD9hiTbOxIbO/networks/os-mastermap-highways-network-core-principles/os-mastermap-highways-network-overview.md).


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