The Lesse tunnels underground for some 8km to form a magnificent cave system that is the region’s biggest tourist draw. Guided visits (English often available) start after a 10-minute ride in a charmingly rickety open-sided narrow-gauge train. Then you take a 2km guided stroll through a succession of impressive subterranean galleries, each well endowed with stalactites and especially fine draperies (beautiful translucent ‘curtain’ formations). The climax of the visit is a short sound-and-light show and a cave whose stalactites reflect beautifully in the water.
Gradients and steps aren’t especially challenging, but dress appropriately (13°C) and allow around two hours. May to August departures are every half-hour, dropping to hourly in the off season. The ticket office is on the main square facing Han’s grey-stone church and a tourist office that rents out bicycles.