The Caves of Han-sur-Lesse (in French: Grottes de Han-sur-Lesse or simply Grottes de Han) are a major
Belgian tourist attraction (around half a million visitors per year) located on the outskirts of the village of
Han-sur-Lesse.The caves are the result of the underground
erosion of a
limestone hill by the river
Lesse. The river forces its way under the hill over a distance of over one kilometer as the crow flies. The caves have a constant temperature of 13°C (55°F) and a high level of humidity. Access is only possible via a vintage
streetcar which departs from the center of Han-sur-Lesse. The entry to the caves is about 2 km from the village. The guided tour takes about an hour to an hour and a half and includes a
sound and light show in one of the largest chambers and a short boat ride ended with a cannon shot do demonstrate the cave's
acoustic properties.
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