The most impressive of the show caves near Dinant, La Merveilleuse features dramatic underground waterfalls, thousands of fine, needle-like stalactites, and several large flowstone formations. The 45-minute guided tour leads you through a series of chambers along a path beside the underground stream.
Entrance is about 500 metres uphill from the railway station; bring a jacket as the temperature inside is about 12°C year-round. Open April to mid-November, daily from 11am to 5pm (until 6pm in July and August). Tours run in French, with English explanations available on request.