# Vector tiles overview

OS Open Rivers is supplied as a national vector tileset 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).

## 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 included here map the GML attribute name its vector tiles equivalent for the WatercourseLink and HydroNode features.

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


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.os.uk/os-downloads/~/changes/AJZwzCsyrD9hiTbOxIbO/networks/os-open-rivers/os-open-rivers-technical-specification/vector-tiles-overview.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.