) | |
| Observatory code | 034  |
|---|---|
| Location | Rome, Roma Capitale, Metropolitan City of Rome Capital, Lazio, Italy |
| Coordinates | 41°55′21″N 12°27′09″E / 41.9225°N 12.4525°E |
| Website | www |
)  Location of Monte Mario Observatory | |
 Related media on Wikimedia Commons | |
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.