It covers the whole national territory and is provided in matrix format to external users. The DTM was obtained by interpolating IGMI orographic data. The resulting product is a 20-m regular-grid matrix, whose elements (pixel) indicate elevation values. Plane coordinates are given in the UTM-ED50 system within the related time zone. Matrix data are available to be purchased in ASCII or BINARY format. The format for sale is the “tile,” which is the subdivision of the national territory, in the two time zones, into areas measuring 10Km x 10Km (purchasable online). In addition to the 20m resolution grid, DTMs are available with geographic coordinates at 1″ and 3″ arc-second resolution, covering a section area at scale 1:25,000 and a sheet area at scale 1:50,000 in the ED50 reference system, respectively (but the latter are not purchasable online).