From Authon, take the forest track that starts north of the village. Park on a small lay-by on the right-hand side of the road, by the stream.
(S/E) From the lay-by, ford the stream and join the path that starts on the other bank.
(1) At the edge of a track that you should leave on your left, turn right and continue south-west along the path. Make a hairpin turn to the left and continue along the ridge.
(2) At a fork, continue straight on the Crête de Pierre-Mont (ignore the path that branches off to the right). The ridge widens and flattens out (a good place to take a break). Continue along a path that is sometimes poorly marked but compensated for by a few cairns, taking care to stay roughly on the ridge line, until you reach a large grassy area with gentle terrain.
(3) Follow the path or cut across the meadows, making sure to head north towards the Coste Belle cliffs.
(4) At the edge of the cliffs (sometimes rocky areas, sometimes just a steep grassy slope), continue north-east. The route passes close to the edge on the left, but is not dangerous (keep a safe distance). Continue towards the summit on a path that often disappears, but just keep climbing with the cliffs on your left. Reach the summit, a vast meadow offering a magnificent 360° panorama.
(5) Continue north on the clearly visible, direct path to the summit of Coste Belle.
(6) Continue north-west on a fairly well-marked path. Cross a fairly wide, grassy passage between two prominent hills. The path becomes clearer and clearer, sometimes cutting into the rocks but presenting no difficulty. After a fairly long descent along the ridge, you will reach an intersection near some trees.
(7) Take the path that descends to the left. Follow a few steep switchbacks in a rocky area and continue west on the straight path of Crête de Raus.
(8) At Col de la Sapie (gate), at the trail junction, take the clearly visible trail that descends to the left, heading due south. Follow the trail as it winds down the sometimes steep slope to a vehicle track.
(9) Follow the track to the left. At an intersection, continue straight ahead (south). Stay on this wide forest track downhill along the valley, ignoring the side tracks. This will take you back to the starting point (S/E).
