 From the south, the climb starts at Lanslebourg-Mont Cenis and is in length, ascending at an average grade of 4.2%.The final starts at Bonneval-sur-Arc and rises at an average gradient of 7.3%, with several sections in excess of 10%.On both sides of the Col de l'Iseran, mountain pass cycling milestones mark the distance to the summit, the current altitude, and the average slope in the following kilometre.