> 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/water-portfolio/os-open-rivers/os-open-rivers-overview/coverage-and-file-sizes.md).

# Coverage and file sizes

## GML <a href="#id-3.3.1-gml" id="id-3.3.1-gml"></a>

* A zipped file comprising a national dataset.
* The zipped file contains one GML file, which contains two feature types.
* The file size is approximately 40MB zipped.
* The data is not encrypted.

## Esri shapefile <a href="#id-3.3.2-esri-shapefile" id="id-3.3.2-esri-shapefile"></a>

* One zipped file comprising a national dataset.
* The zipped file contains two shapefiles.
* Each shapefile holds a single feature.
* The file size is approximately 40MB zipped.
* The data is not encrypted.

## GeoPackage <a href="#id-3.3.3-geopackage" id="id-3.3.3-geopackage"></a>

* A zipped file comprising a single national GeoPackage file.
* The GeoPackage file contains two individual layers for each feature type, both with national coverage.
* The file size is approximately 60MB zipped.
* The data is not encrypted.

## Vector tiles <a href="#id-3.3.4-vector-tiles" id="id-3.3.4-vector-tiles"></a>

* A zipped file comprising a single national MBTiles file.
* The MBTiles file contains a full set of national vector tiles, with options available to split these out into individual tiles as PBF files.
* The file size is approximately 130MB zipped.
* The data is not encrypted.


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