This grandiose Franciscan church is one of the masterpieces of Italian Gothic style and is the work of Arnolfo di Cambio who started it in 1294.

The rather cold façade, however, belongs to the 19th century and Niccolò Mathas. The interior is splendid, with its sweep of pointed arches towards the apse and the large mullioned windows. The ceiling of the nave in keeping with Franciscan tradition is a simple arrangement of roof trusses.