On the hill of the Campidoglio in central Rome, at the top of a steep staircase of no less than 124 steps, stands the church of Santa Maria in Ara coeli. The present church was built in the 12th century, but a church had been present on the site since the 9th century, built on the ruins of a temple dedicated to Juno Moneta.
Legend has it that on these very slopes the female prophetess known as the Tiburtine Sybil predicted the coming of Christ to the Emperor Augustus: "HAEC EST ARA FILII DEI," – “here is the altar of the son of God” … hence its modern name Ara Coeli (heavenly altar).
Just a few steps from the church of Santa Maria in Ara Coeli, in the Great Hall, also known as the Horatii and Curatii Room, the Treaties of Rome were signed on March 25 1957. They are considered to be the ‘birth certificates’ of a united Europe.