Monte Mario Observatory

The Monte Mario Observatory (Sede di Monte Mario, literally "Monte Mario Site") is an astronomical observatory and is part of the Rome Observatory (Osservatorio Astronomico di Roma). It is located atop of Monte Mario in Rome, Italy. This location (12°27'8.4"E ) was used as the prime meridian (rather than Greenwich) for maps of Italy until the 1960s.

Astronomical observatories in Italy
Arcetri Observatory Asiago Astrophysical Observatory Brera Astronomical Observatory Cagliari Observatory Astronomical Observatory of Capodimonte Catania Astrophysical Observatory Collurania-Teramo Observatory European Gravitational Observatory Giuseppe Conzo's Observatory Helmut Ullrich Astronomical Observatory International Latitude Observatory Medicina Radio Observatory Merate Astronomical Observatory Monte Mario Observatory Noto Radio Observatory Orioloromano Observatory Osservatorio Ximeniano Panzano Observatory Pistoia Mountains Astronomical Observatory Rome Observatory San Vittore Observatory Observatory of Turin Trieste Astronomical Observatory Vatican Observatory