Started in the late 13C, building of the fortified cathedral was only properly completed in the 14C. In the Gothic style and built on the site of an initial edifice incorporated in the defensive ramparts, it underwent a huge rehabilitation project in 2000. Visitors can see the works completed so far and get a close look at the pieces undergoing restoration (the itinerary varies according to the progress of the works). This entirely innovative initiative enables you to discover the secrets of this fortress-temple and help you understand the development and urban plan of the town's historic district.