The bell tower stands at the town’s highest point, in the scenic and charming central square on the site of its former castle. Note the remains of the perimeter walls (11C-12C) of the castle of the counts of Hainaut (12C) and the chapel of St Callistus with Romanesque crypt (11C). The 87m-high belfry is unique in Belgium for its Baroque style. It is topped by fine onion dome and an openwork lantern. It has 49 bells, the heaviest weighs 5t.