# Vector tiles overview

OS Open Roads is supplied as a national vector tile set in a single MBTiles file. This is a lightweight set of tiles that are efficient and fast to render in your software, provide high-resolution data and give 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 file is very similar as the vector tiles set within the MBTiles file is not limited in the number of characters for an attribute name. The tables on the following pages map the GML attribute name to the attribute name in the vector tiles:

* [RoadLink](https://docs.os.uk/os-downloads/products/transport-network-portfolio/os-open-roads/os-open-roads-technical-specification/vector-tiles-overview/roadlink)
* [RoadNode](https://docs.os.uk/os-downloads/products/transport-network-portfolio/os-open-roads/os-open-roads-technical-specification/vector-tiles-overview/roadnode)
* [MotorwayJunction](https://docs.os.uk/os-downloads/products/transport-network-portfolio/os-open-roads/os-open-roads-technical-specification/vector-tiles-overview/motorwayjunction)

{% hint style="info" %}
An asterisk symbol (\*) in the tables indicates that a particular attribute is not available in vector tiles (for example, the fictitious attribute is available in GML, but not in vector tiles).
{% endhint %}

## Vector tiles schema

The vector tiles schema, as well as the attribute zoom levels, is detailed in the following three tables. The zoom levels columns indicate whether or not the specified layer and attribute are displayed within that zoom level (*Y* – yes, *N* – no).

### RoadLink layer

<table data-full-width="true"><thead><tr><th width="275">Attribute</th><th width="163">Zoom Level: 0 to 8</th><th>9</th><th>10</th><th>11</th><th>12</th><th>13</th><th>14</th></tr></thead><tbody><tr><td>id</td><td>N</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td></tr><tr><td>road_classification</td><td>N</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td></tr><tr><td>road_function</td><td>N</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td></tr><tr><td>form_of_way</td><td>N</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td></tr><tr><td>road_classification_number</td><td>N</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td></tr><tr><td>name_1</td><td>N</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td></tr><tr><td>name_1_lang</td><td>N</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td></tr><tr><td>name_2</td><td>N</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td></tr><tr><td>name_2_lang</td><td>N</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td></tr><tr><td>length</td><td>N</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td></tr><tr><td>primary_route</td><td>N</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td></tr><tr><td>trunk_road</td><td>N</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td></tr></tbody></table>

### RoadNode layer

<table data-full-width="true"><thead><tr><th width="151">Attribute</th><th>Zoom Level: 0 to 8</th><th width="66">9</th><th>10</th><th>11</th><th>12</th><th>13</th><th>14</th></tr></thead><tbody><tr><td>id</td><td>N</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td></tr><tr><td>form_of_road_node</td><td>N</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td></tr></tbody></table>

### MotorwayJunction layer

<table data-full-width="true"><thead><tr><th width="151">Attribute</th><th>Zoom Level: 0 to 8</th><th width="66">9</th><th>10</th><th>11</th><th>12</th><th>13</th><th>14</th></tr></thead><tbody><tr><td>id</td><td>N</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td></tr><tr><td>junction_number</td><td>N</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td><td>Y</td></tr></tbody></table>


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