As the highest mount in Rome, Monte Mario is the ideal location for the study of the stars. The Monte Mario Observatory was constructed for just that purpose, giving astronomers a clear sight of the night sky above Rome. The peak of Monte Mario was used instead of Greenwich as the Prime Meridian for Italian maps until the 1960’s.
Monte Mario is also home to a nature reserve on the east side, and an upscale district on the west. It also showcases the Santa Maria Rosario church. Though Monte Mario is currently the highest point in the city, it is not considered one of the seven hills of Rome because it lay outside of city limits when Rome was built on the iconic seven hills.