Park your car along the D242 (there's room for 3 or 4 cars), near the sign for "Abri de la Peyrouse".
(S/E) Walk up the paved road WNW for 50m, then make a left on a wide path marked with yellow and green signs. Ignore all trails branching out, and follow this path up to the "Grand Clos" meadow. The first rays of sunshine should start shining on the top of the Vercors cliffs if you have left on time.
(1) The path keeps climbing steeply going straight West under a beautiful canopy of tall trees.
(2) At a large isolated boulder (which probably came down from the cliff), leave the large path to turn left on a smaller trail that zigzags through the forest up to the Peyrouse shelter ("Abri de la Peyrouse").
(3) With your back facing the shelter entrance, take a right (SW) on a path climbing towards the foot of the cliff (the "balcon Est du Vercors" main trail heads South and is on your left).
After a few sharp turns , the path (E) reaches a meadow - "Pré de Serre Brion" - and the cliff base (1850m).
(4) Put your helmet on and, depending on time of the year, slide your ice axe under the shoulder strap of your backpack: from then on, the trail gets more challenging. A few steps on the rocks lead you to the staggering ledge (B) heading due South towards the foot of Serre-Brion pass. If you come across névés, don't hesitate to climb around them through easy rocks towards the ledge.
Go South on that ledge. After a prominent shoulder, the path goes down for a few metres just before hitting the base of the Serre-Brion couloir. As the slope is fairly steep (30º to 45º), put your crampons on and keep your ice axe at hand before climbing up this couloir. Mid way up, it divides in 3: follow any of the 2 left branches heading South to exit at the lowest point on the ridge, i.e. Serre-Brion pass.
(5) Once your crampons and axe are safely stowed away, head North along the ridge until you reach the Morta pass (sign). Try to go through each intermediate summit, as they offer a range of stunning views. In particular, just before reaching Etoupe pass (about half way between Serre-Brion and Morta passes), turn back to see the Œil du Gorille (C), a small arch within the steep rock face of the "Rochers de la Peyrouse".
Both Etoupe and Morta passes are well marked and it is hard to miss them as long as you follow closely along the crest of the cliffs; you can't get lost, even if there's a bit of fog.
(6) At Morta pass, go down, due East. You may need to put your crampons on again, in case snow is still present and hiding the path. If this is the case, a safe process is to chimney down with your back to the rocks and your crampons in the snow.
(7) After going down through a few hairpin bends, go due South, back to Peryouse shelter.
(3) From there on, retrace your steps back to your car (S/E).