A Romanesque church with a nave, tower and semicircular apse with windows. The south facade has an atrium. Its doorways combine flat archivolts and moulds on columns. Within the church there are striking windows and high arches resting on twin columns in the walls. Also noteworthy is the Gothic chapel of the Campo family and the important paintings by A. Benson and J. Pontormo. Under the apse there are remains of an earlier church.