The current high altar, in marble, replaced the wooden altar in the eighteenth century. It’s an anthology of different styles. The apse wall between two bell towers, of Romanesque tradition, corresponds to a roof domes of Byzantine inspiration. The interior, with various chapels, also shows a composite architecture.

Overlooking the port and built between the twelfth and thirteenth centuries, the church is built in stages. It is enriched with numerous chapels from the thirteenth century and it is the subject, over the centuries, of renovations and restorations.