It’s best just to contact us and ask, if you’ve not been able to find out from colleagues. Or if you’re not sure of the exact extents of an existing grid, or are trying to work out if it will be valid on a branch line or a neighbouring highway, for example, that was not part of the original design.

Give us as much information about the project as you can, as there are places where more than one SnakeGrid overlap, each covering a different extent. We’ll let you know if something already exists and can usually help to put you in touch with the people who originally commissioned it.