(S) From the Pré Peyret hut, take the mainGR® trail and follow it all the way to the Col du Rousset.
(1) Do not descend into the resort but follow the contour line (this is theGR®) to reach a small pass at the foot of the But de la Neve (you are just above the Col du Rousset tunnel).
Descend to reach the road (which is just below) via a descending traverse. Leave the road and take a path on the right (signposted for a via ferrata); follow a good, sloping path carved into the cliff face to reach a pasture with signposts at the small pass.
(2) Turn left and climb towards the Chironne rocks and the ridge, crossing out from beneath the summit.
(3) Follow a well-marked, clear track along the ridge.
Caution here: this entire section is close to the edge; take care of the ledges and, if visibility is poor, allow for a safety margin by keeping slightly lower down on the right-hand side.
Pass beneath the But de l’Aiglette to the large meadow, the upper part of which forms the Col de Vassieux.
(4) Continue to follow the ridge; shortly afterwards, a well-marked path branches off horizontally to the right, leading in 5 minutes to the Col de Vassieux refuge (E), today’s destination.