Lac de Derborence

Lac de Derborence is a mountain lake in the Swiss Alps, located in the canton of Valais and set in a steep, forested valley. It is notable for having been formed and enclosed by large historical rockfalls, which block the valley downstream.

Trails around the lake and through the adjacent woodland provide direct views of the cliff faces and the talus fields that created the basin; the site is frequented by hikers and nature observers. The valley’s steep limestone slopes and mixed forest create a compact alpine landscape rather than broad open water.

Large-scale rockfalls in the early 18th century deposited the debris that dammed the valley and created the lake; the resulting accumulation of boulders and forested slopes remains the site’s defining feature. The lake and debris fields are preserved within a relatively remote mountain setting.

The lake lies in Valais, in a side valley of the upper Rhone basin, and is accessed on foot from nearby alpine roads and villages in the canton.

• Trail access: The lake basin occupies a narrow, steep-sided valley and is reached by footpaths that run through forest and alpine meadow; the area is known for rockfall debris and cliff scenery.