On the site of the former Castle of the Counts of Hainaut, the Castle Square provides an ideal viewpoint from which to discover the panorama of Mons and its region.
Oldest religious monument in Mons, the Saint Calixte's Chapel (1051) houses the Museum of the Count's Castle (archaeological discoveries, medieval iconography...). Copies of the recumbent effigies of Philip VI of Valois (1328-1350) and of Charles V, the Wise (1364-1380) have been kept in the crypt.