The city center and ramparts are easily navigated on foot. Twenty minutes takes you straight across town.
Go swimming at "Halve Maan" provincial open air swimming pool. A wonderful place to wile away a sunny afternoon in this lazy town.
Walk the old city ramparts, a very green belt around the city. It easily connects into the surrounding countryside.
Take a parachuting class in the nearby (4 km) Schaffen airport, which doubles as training grounds for the Belgian paratroop regiment.