Monte Mario Observatory
Template:Infobox 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.
de:Osservatorio Astronomico di Roma Sede di Monte Mario