Data identifying linear features (shown as polylines) representing geological faults at the ground or bedrock surface (beneath superficial deposits). The scale of the data is 1:250 000 scale providing a generalised set of linear features. Onshore coverage is provided for all of England, Wales, Scotland, and the Isle of Man. Geological faults occur where a body of bedrock has been fractured and displaced by large scale processes affecting the earth's crust (tectonic forces). The digital data are attributed by fault type; two categories of fault are described in the data: contact and non-contact faults. Contact faults form a boundary between two different rock types whilst non-contact faults indicate a fault displacement within the same rock. The data has been generalised and shows only the location of major faults. All faults shown are inferred i.e. not exposed or seen at a locality, but derived from other evidence including linear depressions in the landscape, the truncation or displacement of topographical features. The data are available in vector format (containing the geometry of each feature linked to a database record describing their attributes) as ESRI shapefiles and are available under BGS data licence.