Visitors come from Brussels and even further afield to see the caves. At least to see the first couple of hundred meters of the caves and by boat. No-one dare venture further into the unknown, where the huge unstable rocks present an uninviting picture. The villagers, however, push forwards. Eventually they discover the magnificent Dome Room and the Arms room.
Further progress is rendered impossible by the river which blocks their path.
Half a century later, after many attempts, the villagers led by the local priest finally find a way to enter the hill on one side and to emerge on the far side. On their route lies the beautiful cave that the tourist today sees on his trip through the caves. The mystery of the course of the Lesse, however, remains unsolved. It reappears here and there in the caves only to vanish again on a gorge under the rocks, where it cannot be followed. That is until the invention of the divers suit and aqualung.