Start at the yellow signpost at the top of the Combatseline chairlift and follow the ancien Bisse de Chervé. This is the highest and most alpine bisse in the region, with its path entirely above 2,200 metres in altitude. It no longer in use and includes some steep and vertiginous passages.

Enjoy the view of the turquoise waters of the Cleuson dam and continue along this old bisse in the direction of the St-Laurent mountain cabin, where you can have a bite to eat.

Then continue on the path towards the Grand Désert lake. This red and white marked trail requires both technique and stamina to reach the mountain lake and its rocky and mineral world.

Return downhill to the Cleuson dam by the same route. Then walk along the Cleuson lake. Cross the wall, then follow a steep path on the right which zigzags down below the dam.

Once you reach the foot of the dam, follow the signpost towards «Siviez».