After the first 500m on the flat, head for the meanders of the Fours Stream which comes from the Méan Martin Glacier, near Col de la Rocheure. At the junction, turn due east into the Fours Valley. It takes at least a good hour to climb the trail to the pass at an altitude of 2976m. The last 100m, a little rocky, are marked by cairns. At the top of the Col des Fours, the panorama is well worth taking in over the peaks of the Tarentaise on the west side and those of the Haute Maurienne located on the east side. On the left, the path which overlooks the Grand Fond Lake descends diagonally to the pass. The cairned path follows the knoll between L’ouille de la Jave on the right and Lake Jave on the left. 100m before arriving at Pont de la Neige, turn off to the south-east.

Follow the GR5 which overlooks the gorges of the Lenta Stream. At the place known as “Le Golaillon” 2345m, head up 125m on the side to the D92 road. Cross the Pont de l’Ouilleta (bridge) to join the GRdp de Haute Maurienne. The path overlooks the alpine chalets and their herds of cattle which are kept around 2100m. The route is slightly uphill to Plan des Eaux (2695m).

Wonderful belvedere path with views of the glaciers of the Haute Maurienne. From Pointe des Arses to Col des Reys, streams run down this southern slope. This is the domain of the herds of sheep that spend summer here. But it’s not uncommon to come across herds of chamois. After 3.5km of traverse, the path bypasses Ouille des Reys towards the north-east to face the superb Montet Waterfall. The slope turns downhill to the small 2603m bridge which is located below the gorgeous little Lac du Pys.

After more than 5 hours on the trail, walk with the sheep while fully appreciating the border cirque which gives rise to the Arc River. To the left of the springs, take the Plan Sec, which is the start of the final climb to the Carro Refuge. The 160m of uphill slope is south-facing. The route crosses the path which descends to the right towards the superb dry stone hamlet of Lécot and which arrives at its administrative centre Bonneval sur Arc. Shortly before arriving at the refuge, the grass disappears and takes on a rocky character.