# Vector tiles overview

OS Open Rivers is supplied as a national vector tile set in a single MBTiles file. This is a lightweight set of tiles that is efficient and fast to render in your software, provides high-resolution data and a seamless experience when zooming in and out. The data is supplied in Web Mercator projection (ESPG:3857).

The vector tiles schema as well as the zoom level for each attribute is detailed on the [Vector tiles schema page](/os-downloads/products/water-portfolio/os-open-rivers/os-open-rivers-technical-specification/vector-tiles-overview/vector-tiles-schema.md).

## Attribute mapping <a href="#id-6.2-attribute-mapping" id="id-6.2-attribute-mapping"></a>

The naming of attributes between vector tiles and GML is very similar as the vector tiles (set within the MBTiles file) do not limit in the number of characters for attribute names. The tables in the following pages map the GML attribute name its vector tiles equivalent for the WatercourseLink and HydroNode features:

* [WatercourseLink](/os-downloads/products/water-portfolio/os-open-rivers/os-open-rivers-technical-specification/vector-tiles-overview/watercourselink.md)
* [HydroNode](/os-downloads/products/water-portfolio/os-open-rivers/os-open-rivers-technical-specification/vector-tiles-overview/hydronode.md)

{% hint style="info" %}
The use of an asterisk symbol (\*) in the tables indicates that a particular attribute is not mapped in that format (for example, the fictitious attribute has no vector tile equivalent).
{% endhint %}


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