From Col Ferret (Swiss border), the valley runs down, beneath the Pré de Bar glacier and the towering Grandes Jorasses peaks. The stream running through the valley is the Dora di Ferret (), which, near La Palud (in front of the Italian Mont Blanc Tunnel exit), joins the Dora di Veny () flowing down from Val Veny to form the Dora Baltea, a left-hand tributary of Po