OS legacy control data

Search for passive stations, benchmarks, or triangulation stations, and find out about the accuracy of our legacy control data

Legacy data tools

Access legacy data, which is no longer maintained, via our search tools for passive stations, benchmarks or triangulation stations.

  • Benchmarks

    Search for OS benchmarks that record height above Ordnance Datum.

  • Passive stations

    Search our database of about 900 Passive GPS stations covering Great Britain.

  • Triangulation stations

    View the archive coordinates supplied for triangulation stations across Great Britain.

  • Datum height differences

    Read the difference between height datum between Liverpool in 1844 and Newlyn (ODN). This allows for the difference at a location to be searched for.