Start of the walk: the Croix de Chamrousse (2,250 m). From Le Recoin station (1,650 m, Chamrousse), access by cable car (€10.50 in 2026) or on foot for the more adventurous.
(S/E) Set off eastwards towards the Robert Lakes. Pass the Col des Trois Fontaines and then reach the Col de la Botte.
(1) Carry on straight ahead to climb La Botte. The path is clearly visible, with a few rocks to cross without difficulty. You’ll reach the rounded, grassy summit. Take in the 360° view.
(2) Head to the right, towards the south. Descend along the wide, grassy, undulating ridge. Look out for Lac de l’Infernet below on the right, which you will be heading towards. The ridge then narrows (about 400 m from the summit), becoming rockier and more wooded. Look out for a scree gully on the right which you can take to reach the lake, but it is better to continue for about thirty metres along the ridge to find a clearing between the trees.
(3) Descend sideways down the mountainside heading north through a grassy area which joins the scree gully further down, at its least steep section. Take care not to slip. Reach Lac de l’Infernet by following the bed of the Ruisseau de Moirin. Explore the area. To the west of the lake, join the path leading down from the Col de l’Infernet. You’ll reach a Y-junction.
(4) Turn left, heading south, and follow the path through the middle of a meadow as it approaches the cliffs. At the end, turn right; after a gentle climb, the track becomes less visible in the grass, but you must stay close to the line between the cliffs and the grassy mountainside. Look out for a large rock higher up on the right with an opening in the middle.
(5) Follow the track leading in that direction to reach the stony, wooded summit. Head left and walk for about 100 m along the ridge. You’ll see an opening and a path on the right (just before the 2030 mark).
(6) Follow this path, which winds in short hairpin bends; it is steep and slippery at the start. Take great care. After a fork to the left, you’ll come to a steep but more accessible path that leads to Lake Achard, which you should walk along on the left-hand side. Cross the bridge at the southern end of the lake.
(7) Follow the signs for Roche Béranger (yellow markings), indicated by a signpost. The path alternates between flat sections and rocky sections which can be crossed without difficulty. On leaving the forest, walk alongside the artificial lake of Roche (or Lauze) and arrive at the Route de la Croisette (Roche Béranger 1,750 m).
(8) Follow the D111a road to the left and continue down it all the way to a Fork in the road. Carry on straight ahead on the D111a towards the technical services, Rue des Brokentins. At a right-hand bend, after the last chalet, look out for a path leading down to the left.
(9) Follow this path, then turn immediately right towards the north onto the Chemin du Renard, which leads to the Le Recoin resort (1,650 m) and the starting point of the walk (S/E).