On the D70, take the D70B departmental road towards the Blache neighbourhood. Pass the recycling bins and park on the left-hand side of the gravel path, which is the starting point for the hike.
For the entire hike, follow the yellow and green markings.
(S) Follow the marked path to the south-west, towards Les Vingt-Cinq.
(1) After about 800 metres, leave the first path on your left and, 100 metres further on, ignore the second path, also on your left. Continue for about 50 metres and take the path on the left that descends into the valley. Follow it for about 900 metres to reach Les Vingt-Cinq.
(2) At the signpost for Les Vingt-Cinq, turn right and then immediately right again. Climb back up towards Perrache on the path parallel to the one you have just taken. After about 500m, leave the path on your right and keep heading north. After 200m, ignore the path on the left and stay on the most marked path for about 1.7km.
(3) At the crossroads, take the path opposite. Follow it to the summit (1076m). Once on the plateau, keep to the yellow and green markings and follow a fence southwards.
Enter the forest and stay on the main path, keeping south to reach Perrache.
(4) At the Perrache signpost, turn left towards Lozeron.
(5) After about 400m, at the signpost at an altitude of 802m, leave the path on the right and continue straight ahead towards Les Vingt-Cinq.
(2) At the Les Vingt-Cinq signpost, to return, follow the same route you took on the way there.