Lake Derborence was formed in 1749 after two landslides coming from the south wall of the Diablerets. Thousands of tons of rock came crashing down from a height of 1900 metres in 1714 and 1749, coming to 400 metres below and forming a 2 kilometre-long natural barrier which gradually filled with water. A virgin forest grew on the rock debris. It consists of spruce, pine, larch, stone pine, beech and willows. The area was acquired by Pro Natura in 1961 and is now protected.