> 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-mastermap-sites-layer/os-mastermap-sites-layer-known-data-issues.md).

# OS MasterMap Sites Layer Known Data Issues

## Live known data issues

| Data Issue Name                                                                                                            | Data Issue Description                                                                                                                                                                                                     |
| -------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Access Point features not intersecting the edge of the associated Functional Site                                          | There are **23** instances of Access Point features not intersecting the edge of the associated Functional Site, whereby the Access Point geometry is between 5m and 100m in distance from the referenced Functional Site. |
| Access Points referencing Road Nodes that do not exist in the latest OS MasterMap Highways Network – Roads product release | Currently, **103** Access Points reference Road Nodes that do not exist in the latest OS MasterMap Highways Network – Roads product release, although this error is often due to the timing of the releases not lining up. |

{% hint style="info" %}
To report an issue not currently listed here, please visit the ['Contact us' page on the OS website](https://www.ordnancesurvey.co.uk/contact-us/business-government/use-os-data).
{% endhint %}


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