HISTORY
The origins of the parish are unknown, but it was probably built on an earlier pagan temple. According to tradition it was built by San Leone, a skilled stonecutter and considered to have been the first bishop of the city. From a door close to the façade, the shrine of San Leo is accessible (3-4th century), where a 8th-century sarcophagus is preserved, decorated with two peacocks drinking. The church is a beautiful example of Lombard-pre-Romanesque of the 9th century, built on the rock of the mountain, in sandstone, limestone and other materials.

ART-HISTORICAL NOTES
The exterior wall of the church is punctuated by pilaster strips, which rest on a socle. On the sides, two round-arch portals are surmounted by a blind loggia with two arches composed of white and red alternating stones. These pseudo-loggias recall the Byzantine architecture of Ravenna. The interior is three-aisled, covered by a wood-trussed ceiling, subdivided into seven bays by a round arcade, with thin pilasters and columns above. The Corinthian columns and capitals are spolia. The three apses are in the east, and the central one is more than twice as big as the lateral two. The church is illuminated by a large double-lancet window in the nave and three single lancets in the apses.
The choir is 1.5 meters above the nave, accessible via a stair. In its center sits an elegant ciborium of 882, held up by four marble columns with capitals. The crypt is below the choir, illuminated by three small lancets and was totally restored in the 1930s, as was the rest of the church. These restorations allowed the recuperation of the building’s original Romanesque structure. The church interior is relatively unadorned and completely in stone, allowing visitors to immerse themselves in an atmosphere of peace.