Grottes de Han
The magnificent Han Caves, which had provided refuge for threatened tribes since Neolithic times, were only rediscovered in the mid-19th century. To tour them, board an ancient tram in the center of Han-sur-Lesse that carries you to the mouth of the caves. There multilingual guides take over, leading groups on foot through 3 km (2 miles) of dimly lighted chambers. You get occasional glimpses of the underground River Lesse as you pass giant stalagmites and eventually enter the vast cavern called the Dome, 475 feet high, where a single torchbearer dramatically descends the sloping cave wall. The final part of the journey is by boat on the underground river. The trip takes about 75 minutes, and involves a total of 365 steps. The cave is 9°C (48°F), with 90% humidity, all year long, so consider bringing a sweater with you. Your ticket also includes entry to PrehistoHan (Rue des Grottes 46, Han-sur-Lesse), an exhibition of the many archaeological finds unearthed within the cave system over the past 60 years.