> For the complete documentation index, see [llms.txt](https://docs.os.uk/osngd/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/osngd/code-lists/code-lists-overview/structurevalue.md).

# structurevalue

This code list is used in association with the Structure attribute which is present within the Railway Link Feature Type. The code list describes the location of the railway relative to the surrounding topography.

| Label           | Definition                                                                                                                                                                                              |
| --------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| In Building     | A Rail Link that is located inside a man-made structure suitable for rail rolling stock.                                                                                                                |
| In Cutting      | A Rail Link that is located where excavation of earth material has taken place to lower the ground level to allow a railway to pass at an acceptable level and gradient through the surrounding ground. |
| In Tunnel       | A Rail Link located in a long tunnel passage under ground to permit the transit for rail rolling stock.                                                                                                 |
| On Bridge       | A Rail Link that is located on a man-made structure that is built over a river, railway, road or ravine to permit the transit for rail rolling stock.                                                   |
| On Embankment   | A Rail Link that is located on a man-made construction, normally using earth and hard aggregates, that allows railway lines to pass at an acceptable level and gradient over low lying ground.          |
| On Structure    | A Rail Link that is located on a man-made structure that is built over a river, railway, road or ravine to permit the transit for rail rolling stock.                                                   |
| Under Structure | A Rail Link that is located under a man-made structure that is built over a river, railway, road or ravine to permit the transit for rail rolling stock.                                                |


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