- Close to the cathedral, the castle mound is one of the founding elements of the city. Built in the tenth century, it protected the collegiate potential aggressors. In 1761, a military prison is high. Check out this site perfectly preserved, which just received a vast restoration campaign. From the top of the root ball, an exceptional panorama opens onto the cathedral or the Jesuit chapel.
- Opening hours:
- From 12 May to 30 June and from 1 to 30 September: Monday, Tuesday, Wednesday, Friday from 14h to 18h. Saturday and Sunday from 10am to 12.30pm and from 14h to 18h30. Closed on Thursday.
- From July 1 to August 31: Monday, Tuesday, Wednesday, Friday, Saturday and Sunday from 10am to 12.30pm and from 14h to 19h. Closed on Thursday.