The City Council of Madrid maintains the municipal topographic network as a uniform and precise framework for the coordination of all topographic work and cartographic products carried out in the area of the municipality. In 2020 it has been completely revised and densified to cover new urban developments. As of 2021 it is updated annually. The Topographic Network of Madrid (RTM) consists of more than 5,000 vertices materialized in the field. It is formed by vertices observed preferably by GPS and complementary to classical topography by precision polygonals. It includes the entire municipality of Madrid, except in Monte de El Pardo and Castillo de Viñuelas. It includes boundary markers of the municipal boundary, as well as vertices of other networks. It incorporates a subnet through all the tunnels of the city, so that it guarantees a single reference system both in surface and underground. It relies on the national geodetic infrastructure through the network of GNSS reference stations (ERGNSS) and the High Precision Leveling Network.