The Groot Begijnhof is the finest thing in Leuven, and arguably one of the most beautiful enclosed communities in northern Europe. It is a complete medieval neighbourhood in miniature: a dozen cobbled streets lined with brick and sandstone houses dating from the 13th to 17th centuries, threaded through by the small river Dijle, with a church at its centre. The whole enclave is closed to traffic and has an extraordinary atmosphere of quiet, especially in the early morning or late evening when the students who now inhabit it have retreated indoors.
Walking through the begijnhof is the best way to spend an hour in Leuven. The streets are narrow enough to touch the walls on both sides, the houses vary wonderfully in scale and age, and the Dijle running through the heart of it adds a gentle sound of water. The beguinage is listed as a UNESCO World Heritage Site as part of the Flemish Béguinages group. The church at the centre (Begijnhofkerk) is usually open during the day — it's a plain Gothic hall church with none of the elaborate decoration of Sint-Pieterskerk, but its simplicity suits the place.