The dam wall, built between 1881 and 1890, along the lake of "La Mouche" is 410 metres long and constructed like a viaduct. The 7
km long path around the lake (94 ha) is ideal for a relaxing walk, a cycle ride or a bracing ride on horse back.
The silhouettes of the villages of St-Ciergues and Perrancey and the local hillside forests are clearly reflected on the sparkling surface
of the lake.