Ordnance Survey – Great Britain's national mapping agency
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Ordnance Survey's OS MasterMap contains more than 450 million uniquely identified geographic features, representing real world information down to individual address and street and building level. The data is validated by over 300 surveyors to published quality standards, so you know you are using nationally consistent information.
But it's far more than simply a map, it allows you to access only the data you need, with far reaching benefits in terms of geographic information.
How it works
You choose how to access the data you need via the online service by area, layer or theme according to your specific requirements. OS MasterMap is available in four data layers, which are linked together via a set of common unique references.
- Topography Layer
- Integrated Transport NetworkTM (ITN) Layer
- Address Layer 2, Address Layer and
- Imagery Layer
The Topography and ITN layers of OS MasterMap data need to be used within geographical information systems (GIS), or Computer Aided Design (CAD) database systems. Click here for details Ordnance Survey's Licensed Partners, who offer such GIS systems.
Adding your own data
Each referenced feature within the OS MasterMap layers may be viewed as a building block that allows you to associate your own data or that of others, providing the basis for analysis. Business information can then be shared with assurance that all users are referring to the same location and entity in the real world. This can be critical in many applications, from street crime to civil contingency.
