The Vaudoise town of Vallorbe lies in a valley basin of the river Orbe, directly on the French border. An inconspicuous chalet is nestled against the slope above Vallorbe. It is the disguised entrance to the fortress "Pré-Giroud".
The river Orbe created the Fairy Caves at the Vaudoise town of Vallorbe. The caves constitute a fascinating grotto complex. The round trip tour leads visitors along the subterranean course of the river to stalactites, stalagmites, dripstone structures, columns and to galleries.