Description:
From the parking at Le Laus follow the road south (towards the Col d’Izoard) until it is blocked off. On the left, there should be a ski de fond track which you follow into the valley on the left (south-east). From the hut after a long straight section it bears left and climbs steadily. At around 2052m you should find a small bridge on the right of the track. Take it and then work your way south- west through the trees. As the trees thin out you will see L’Arpelin east face on your right. Continue going south into a small bowl. As the ground starts to rise towards the Cote Belle turn right (west) and make your way to the Col Perdu.
Descent:
Head back the way you came, it is possible to stay on the left-hand bank of the river you crossed for longer and then cross back over to the ski du fond track further down.