To get to the start, cross Collobrières on the D14 and take the road that leads to the Chartreuse de la Verne for about 150m. Park your car in the car park at Croix d'Anselme.
(S/E) Take the tarmac road above the car park for about 300m.
(1) Leave the road and take the path on the left. Follow this path as it winds along the left bank of the Verne. Join the path just before the Retenue de Lambert.
(2) Continue along the path on the right to reach and cross the ford, then follow the Verne river (westwards) for 400 metres. Join the dam track. Continue westwards to reach a crossroads where there is a hunter's hut.
(3) Take the track heading south for about 200 metres until you reach a trail junction.
(4) Take the path on the left heading north-east. Cross the track, then take the small drovers' road heading south which leads to the Pluviomètre track.
(5) Follow this road south-east until you reach two trail junctions.
(6) At the second trail junction, head south-east to the left for about 1 km. This trail is called Route de Lambert. At elevation 524, join theGR®90.
(7) Turn right and follow the red and white markings to return to the previous crossroads.
(6) Continue along theGR®90on the left to reach another trail junction.
(8) Head north-west to reach the Maison Forestière de Lambert. Then keep left to take the Piste des Pounches. You will come to another crossroads near a water source.
(9) Turn right, heading east, for about 1.5km to reach the crossroads before the Lambert Reservoir you passed earlier.
(2) Turn left and follow the same route you took on the way there to return to the car park (S/E).