IGN France – National Institute of Geographic and Forest Information

The Institut national de l’information géographique et forestière (IGN) is France’s national mapping and geodetic agency, headquartered in Paris. IGN is responsible for national mapping, geodetic reference systems, height systems, gravity infrastructure, and the provision of authoritative geospatial data for France and its territories.

In geodesy, IGN plays a central role in the realization and maintenance of the French terrestrial reference frame (RGF), precise GNSS infrastructure, gravity field determination, and leveling networks. IGN is also a key contributor to the International Terrestrial Reference Frame (ITRF) and international geodetic services, supporting global positioning, Earth rotation studies, and Earth system monitoring.

More info: https://www.ign.fr/