The cathedral was built on the site of a temple to Apollo, so the legend goes, between the 5th to the 18th century.
The variety of its architecture is immediately visible on its frontage: to the right, or south, the 12th-century Romanesque gate adjoins a Roman wall, while to the left (north), the huge, richly carved Gothic gate from the 15th and 16th centuries is surmounted to the north by a bell tower erected between 1323 and 1425.
Inside are three naves of different styles (Romanesque, Gothic and Baroque), which flank the octagonal font which rests on a stand dating back to the 5th century.
Its central basin recalls the ancient rite of baptism by immersion. Crossing the chancel, we reach the cloister, built at the close of the 12th century.
It is a place which breathes tranquillity and elegance. Small in size, built with solid galleries, while the rich and varied decorations of the pillars are inspired by the animal and plant kingdoms, by fantasy and by the symbols of the evangelists.
As for the organ, the green and gold case was built by Jean-Esprit Isnard in 1745 and the instrumental part by De Ducroquet dates from 1855 both are listed historical monuments.