From the parking at Puy Chalvin, head west up the road to the bend by the farm. From there it is possible to go north-west straight to the Chapelle St Laurent, or follow the road through Puy Chalvin until it is shut by snow and then follow the track out and back to the chapel.From the chapel follow the road through the hamlet of Les Combes to 1907m, where there should be an obvious bend in the road and a barrier. (This may be covered in snow so be aware of it on the descent if it’s only just sticking out.) Here you are entering a nature reserve so please act accordingly.From there head north-west into the valley until around 2000m. At this point turn left (south-west) and climb until you reach the Col de la Trancoulette. From the col, head east to the Crête du Dos d’Ane de Passaga. Follow this crête to the summit of the Croix d’Aquila.
From the Croix, head back down the ridge until you reach gentler terrain on your right (east). Descend this and make your way towards the Ravin du Clot des Souches. Descend its left bank which will bring you out at the end of the road at 1907. From here you can ski back down the road to Puy Chalvin.