The lake of Longemer is supplied by the Vologne, whose source originates at the foot of the Hohneck. At the heart of the beech woods, the river is divided into several arms forming small islands. Baptized the Marie-Louise Islands, they are connected by small wooden bridges. Further on is the Fairy Bridge, made of stones. The inhabitants used to pass on it trembling. A local legend tells that an evil fairy would have dragged a virtuous man there and that no one ever saw him again.