You can reach the start of the walk by taking a small road that leaves from the entrance to the village of Sappey-en-Chartreuse when arriving from Grenoble and leads to the Fort du Saint-Eynard (signposted).
Park in the small car park 200 m below the fort. A discreet P sign indicates that you should take a small road on the left.
(S/E) Head east towards the rock face. Take the wide rampart walk on the left. Enjoy the view of the city of Grenoble and the meandering Isère river. Reach the end of the rampart walk and note the cave there.
(1) Turn left and climb a small hill to reach theGR®9. Continue to the right, following the red and white markings along the cliff.
(2) Pass Pas Guiguet (sign indicating the direction of Pré du Plat). Stay on theGR® along the ridge. At a fork, turn right.
(3) When you reach the Pré du Plat sign, descend to the left (towards Le Sappey). You will come to a wide track, which you take to the right. This takes you off theGR®.
The track leads you to the top of the Grand Sommard ski lift at a place called Pré du Plat. Enjoy the view of the Sappey valley and the surrounding peaks (from Bec de l'Orient on the far left to Chamechaude on the right).
(4) Return via the same route. Be careful not to pass theGR® on the left. The junction is very discreet. Climb up the embankment.
(3) At the "Pré du Plat" sign, turn right to return to the fort car park (S/E).
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