Crossing the Grande and Petite Moucherolle, from the Deux Sœurs to La Balme

Reach the Col de l’Arzelier either from Vif via Saint-Barthélemy and Prélenfrey, or from Monestier-de-Clermont via Château-Bernard.
Descend a little down the southern slope of the pass to take the small road on the right leading to the resort and continue straight on until the end of the tarmac road to reach the car park, before the barrier on the forest road: a place called Moret.

(S/E) Near the small chalet, take the forest track heading north; it climbs through the forest, then veers eastwards, turns left and eventually emerges from the forest. After a final right-hand bend, you reach the Refuge de la Soldanelle.
(Several alternative routes are possible, either via the ski runs or via an old, unmarked forest path).

(1) At the Refuge, turn left and head westwards up to Pré Achard: a crossroads and a small quarry.

(2) Leave the flat Périmètre path and, above the quarry, take the path that winds northwards up to the foot of the Grande Sœur Agathe cliffs. Follow the base of the rocks to the right until you reach the couloir between the Deux Sœurs.

(3) Here begins the steep, rugged ascent of the Couloir des Deux Sœurs, first via a ledge secured by an old cable, then via switchbacks or more direct climbs, mostly on the left bank (orographic) of the couloir, up to a second ledge opposite an arch, followed by further switchbacks and a few rocks leading out into the notch of the Col des Deux Sœurs (between Grande Sœur Agathe to the south and Petite Sœur Sophie to the north).

(4) The Grande Moucherolle is clearly visible; head towards it via a path due west. It crosses a plateau then climbs increasingly steep slopes via a couloir where you’ll need to use your hands, ending with a rockier ledge and an exposed ridge.

(5) Reach the western secondary summit, which has a belay station, and begin descending the grassy ridge to the north-west. A cairn marks the point where you change direction, plunging down a steep ledge on the west face; traverse south-east to descend again down steep slopes towards the valley. These end in a 4-metre vertical drop, which you must climb down using the good holds available, though these are difficult to see from above.
The path becomes less steep as it reaches the Col des Moucherolles.

(6) Climb the grassy slopes opposite, aiming for the base of a gully cutting across the rock face. This gully is fairly easy to climb, although steep and occasionally exposed. Emerge onto the grassy plateau of the Petite Moucherolle.

(7) Descend the opposite ridge, heading west; the marked path crosses a sharp limestone pavement and then an area of standing cairns to reach, within sight, the arrival point of the ski lifts at the Grand Couloir refuge.

(8) Cross the barriers marking the edge of the ski run to a viewpoint (table) and descend into the grassy valley towards the south-west (no real path) to the foot of the 1991-metre-high hill, the Roche du Coin.

(9) Descend southwards along the cliff edge, towards the clearly visible Pas de la Balme, via a track that gradually becomes a proper path.

(10) At the Pas de la Balme, head south-east to follow a ledge beneath the cliff, which rises slightly before turning beneath the Mur des Sarrasins and a small cave beneath an overhang, then descend a gully via tight switchbacks.
At the end of the couloir, a traverse to the left leads to wider switchbacks on the now grassy slope leading to the junction marked Mulet du Curé.

(11) Turn left to traverse north-east and descend to the path known as the Périmètre, at the sign marked Les Poules.

(12) There are two options:
1) return by following this Périmètre path, which leads to Pré Achard, involving a short climb.
2) the option chosen on the map: take the path branching off to the east beneath the Périmètre path (towards Château-Bernard), which descends via a lovely forest track; make a wide right-hand bend into the Bois Barnière. It crosses a first forest track, then the slope levels off, leading onto a second forest track, which is suitable for vehicles.
Turn left onto it to descend via a wide right-hand bend and join the forest road known as the Dus at the Font Bessou junction.

(13) Follow this level road to the left towards the east, passing the Font du Mas junction.

(14) Continue along this road, which leads back to the hamlet of Mauret (S/E).

The ‘Very Difficult’ rating is due to the difficulty and, in some cases, the exposure of several sections:
- the ascent of the Couloir des Deux Sœurs follows a path that is no longer marked or maintained. It is, in fact, quite overgrown, requiring caution and attention, even though its rock faces are not particularly technical;
- the ascent to the Grande Moucherolle is very steep, with a fairly high final ledge that requires care, even though handholds are available; also watch out for rockfalls in this ascent couloir;
- the descent to the Col des Moucherolles is down a very steep face, with several ledges where care is needed; the last one is only 4 m high but vertical, and the footholds—though clearly present—are not always visible from above;
- The ascent to the Petite Moucherolle follows a fairly short but very steep and, in places, exposed couloir, although it is easier to climb than it appears.

The route is not always signposted, but it is fairly obvious to follow throughout as it is well marked. Only the descent from the Grand Couloir to the Pas de la Balme does not always have a path, but the terrain is easy grassy ground and the Pas de la Balme is visible. In foggy conditions, this can be more problematic.

As the route includes several sections at the foot of cliffs and even overhangs, the GPS track is approximate in these areas and the elevation gain recorded is incorrect (notably at the Couloir des Deux Soeurs and the Pas de la Balme ledge). The total cumulative elevation gain is closer to 1,200 m than 1,600 m.

The Vercors plateau has no water sources; springs are available further down the eastern slope: at the Refuge de la Soldanelle or in the Bois Barnière.

Magnificent views all along the route: you climb the eastern face of the Vercors with the sun rising above the Dévoluy, the Ecrins, the Taillefer, the Grandes Rousses and Belledonne.
From the Col des Deux Sœurs to the Pas de la Balme, the view stretches in all directions, taking in the interior of the Vercors, the Chartreuse, the Southern Jura and the Massif Central.