Begun in 1722 in a pure Baroque style, it was not finished until 1838. The facade is a play of concave and convex surfaces flanked by two towers topped by small temples, resembling two astronomical observatories. 1844 marked the completion of the great roof covering the transept; since then, the dome, on some misty days, seems to float above the town. The inside, in the shape of a Latin cross and ambulatory, is surprising by its size and the quality of light