# OS MasterMap Highways Network Downloads

## Code lists

The [XML code lists for OS MasterMap Highways Network](https://www.ordnancesurvey.co.uk/products/xml-codelists) are available to view and download from the OS website.

## Schema files <a href="#bookmark8" id="bookmark8"></a>

Schema files are used to interpret the Geography Markup Language (GML) files and translate it into a suitable data format by your chosen software; however, we are aware that some firewalls will block access to these. In these instances, it is suggested that you download the schemas from the [OS MasterMap Highways Network GitHub repository](https://github.com/OrdnanceSurvey/OS-MasterMap-Highways-Network-ALL-Schemas).

The [XML schemas are also available to view and download from the OS website](https://www.ordnancesurvey.co.uk/products/xml-resources#os-mastermap-layer-schemas).&#x20;

## Stylesheets

Predefined stylesheets for OS MasterMap Highways Network are available for download from the [OS MasterMap Highways Network Stylesheets GitHub repository](https://github.com/OrdnanceSurvey/OS-MasterMap-Highways-Network-stylesheets). To download a ZIP containing all stylesheets, navigate to *Code*  > *Download ZIP*.


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