Its geographical definition coincides almost exactly with the former cantons of Le Bourg-d'Oisans (Isère) and La Grave (Hautes Alpes).

The Oisans covers parts of the massifs of Belledonne, Taillefer, Grandes Rousses, Arves and Écrins.

The highest point in the region is the mountain of Pic Lory, a subpeak of the Barre des Écrins which reaches a height of 4,088 metres, but the most symbolic peak is la Meije which is nicknamed the "Queen of the Oisans".

The Oisans is a remarkable territory, thanks to its numerous mountain chains, valleys, rivers, streams and plains.

Oisans regularly hosts the Tour de France as well as many major sporting events on a European scale (Super-Biker, World of Snowboarding, Skiing World, the Bike Festival, Andros Trophy or the Criterium Cyclist of Dauphiné Libéré).