A WMS (Web Map Service) is a service that produces maps of spatially referenced data starting from geographic information, and is a technical specification defined by the OGC (Open Geospatial Consortium). This WMS presents the "Administrative Areas" layer of the Bodies' Reference Territorial Database (BDTRE), structured according to national technical specifications (Prime Minister's Decree of November 10, 2011), collects information referring to the main territorial areas of administrative value. This refers to areas with official value and only the main Administrations are taken into account: Municipality, Mountain Community, Province, Metropolitan City, Region, State. The contents of this service are divided into the following levels corresponding to the BDTRE classes:- Local authority administrative areas The maps can be viewed using various software (e.g. QGis)