The ancient parish church, dating back to 758, was destroyed by an earthquake. In 1117 it was rebuilt and consecrated in 1122. The façade faces the South-West and is characterized by interrupted salients;it is divided into three parts by a massive buttress with steps. The three apses, harmonically faithful to Lombardic prototypes, are tripartite thanks to long semi-columns.The interior, simple and austere, is characterized by seven cruciform pillars.On some nights classical music concerts are held in the collegiate church.