It was a cathedral until 1801, when the episcopal seat was moved to the lower town; restorations were carried out by Viollet-le-Duc from 1844. The church has a Romanesque nave and a Gothic transept, choir and apse. In 1096 Pope Urban II blessed the stones intended for the construction of the nave; the style of the portal and several of the capitals suggests that this was built by 1125. The aisled nave has square piers with engaged shafts alternating with circular piers. Between 1269 and 1330 the east end was replaced by a Gothic transept and choir. The impact of Parisian Gothic, especially of the Sainte-Chapelle, Paris, can be recognized here.