Refine your search for walks in Couzon (cours d'eau) - Affluent du Guier
Le Grand Som from the Col du Cucheron
Walker 
8.74 km
+881 m
-880 m
5h 00
Difficult
Departure from Isère
This is definitely the easiest and shortest way to climb the Grand Som.
Caution for those prone to vertigo: between (2) and (3), the walk becomes a climb in places. The passages are often narrow and can be daunting.
Tour of the Saint-Pierre-de-Chartreuse valley
Walker 
13.11 km
+294 m
-291 m
4h 35
Moderate
Departure from Saint-Pierre-de-Chartreuse (Isère)
Leave the village and walk around the valley, discovering the main peaks as you go: Charmant Som, Chamechaude, Dent de Crolles, Scia and Grand Som. You will also pass through several Carthusian hamlets.