Really just a short-cut and and exercise in cutting corners, the Boisses Couloir is nonetheless a cracking little route to play around in quite technical terrain. Cross the wide flat area beyond the start of the Marais chair, aiming towards an obvious col towards the dam end of the lake. The entry to the couloir is obvious and can be quite narrow, depending on snow conditions. The couloir itself is only 50 yards long, and accesses a fun little steep-ish pitch that rejoins the Mélèzes piste.