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Ordnance Survey Ontologies

Ontology Description
Postcode Ontology An ontology describing the postcode geography in Great Britain.
The administrative geography and civil voting area ontology An ontology describing the administrative and voting area geography of Great Britain
Geometry Ontology A ontology to describe abstract geometries.
Spatial Relations Ontology An ontology describing basic spatial relations.
50k Gazetteer An ontology describing the 50K Gazetteer.