Briefly its own principality during the 18th century, Grimbergen has a superb central basilica church sharing a small square with a series of historic houses signed in Gothic scripts. A short stroll south, the leafy Prinsenbos park leads to castle ruins sitting inaccessibly in their moat and a museum of rural craft in the castle's former outbuildings. Just northeast of the centre are a couple of charming watermills linked by a lovely seemingly rural footpath. All this so close to the Brussels ring road makes Grimbergen a very worthy 15-minute detour from the Atomium if you're driving.