> 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/land-and-terrain-portfolio/os-terrain-50/os-terrain-50-technical-specification/vector-tiles.md).

# Vector tiles

OS Terrain 50 contour layers are supplied as a national vector tiles 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 which give a seamless experience when zooming in and out. The data is supplied in Web Mercator projection (ESPG:3857).

For guidance on using the product in vector tiles format, please see the [Getting Started with Vector Tiles guide](/os-downloads/resources/product-resources/getting-started-with-geopackage-and-vector-tiles-guides/getting-started-with-vector-tiles.md).

## Data schema <a href="#bookmark28" id="bookmark28"></a>

The vector tiles schema is detailed in the following table. In the *Zoom levels* columns within the table, the letter *N* indicates that the specified layer and attribute are not mapped within that zoom level, whereas the letter *Y* indicates that the specified layer and attribute are mapped within that zoom level.

### contour\_line

<table data-full-width="true"><thead><tr><th width="192">Attribute</th><th width="175">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>property_value</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>contour_line_type</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>

### spot\_height

<table data-full-width="true"><thead><tr><th width="194">Attribute</th><th width="168">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>property_value</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>spot_height_type</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>

### land\_water\_boundary

<table data-full-width="true"><thead><tr><th width="223">Attribute</th><th width="172">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>property_value</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>water_level_category</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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