Caves of Han-sur-Lesse

The Caves of Han-sur-Lesse (in French: Grottes de Han-sur-Lesse or simply Grottes de Han) refers to a natural complex of caves in Belgium. A major Belgian tourist attraction (around 250-300,000 visitors per year), the caves are located in Wallonia, on the outskirts of the village of Han-sur-Lesse. The caves were formed as the result of an underground erosion of a limestone hill by the river Lesse. For most of its length a meandering river, it abruptly plunges into a sinkhole not far from Han-sur-Lesse. This hole is known as the gouffre de Belvaux (English: the Belvaux abyss), where it forces its way under the hill over a distance of over 1 kilometer (1⁄2 mi) as the crow flies before streaming through the cave complex known as the Grottes de Han.

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