Mont Aiguille stands apart from the rest of the massif as the result of erosion. Other parts are isolated from the rest of the massif due to its relief. For example, to reach Gresse-en-Vercors in the south, one must travel via the col de Rousset or journey via Saint-Nizier-du-Moucherotte in the north. The villages at the far northern end were isolated by a landslide near the Mortier tunnel. Another example is the Peuil plateau in the east. During the Ice Age, the Grésivaudan glacier reached the Peuil plateau leaving a marsh.