 From Le Bourg-d'Oisans the route follows the D1091 through the Romanche valley before joining the D526 after .The climb starts at the Barrage du Verney from where there is a further to the summit, which is reached shortly after the junction with the route to Col de la Croix de Fer.Over this distance, the height gained is ; the average gradient is thus 4.8%, although there are some downhill sections en route and a maximum uphill gradient of 11.1%.