Documents allege a church existed at the site by 756. Of that building, only the baptismal font seems to have survived. The earthquake of 1117 prompted a major reconstuction, and a new building consecrated in 1122. The "Portal of Paradise" retains some of the Romanesque sculptural elements, with a relief depicting Madonna and Child with St Peter and Angels. The portico on the left of the church with octagonal columns, church cloister, and bell-tower, date to the 15th century. The church facade was also completed in the 15th-century. The "Palazzo Pretorio" adjacent to the church was built in 1293. Further reconstructions and additions occurred in 18th and 19th centuries.