Analysing terrain data
The exposure grade does not take into account objective hazards (stone fall, seracs, etc) but only the consequences of the skier falling.
Low Exposure (E1): Exposure is limited to that of the slope itself. Getting hurt is still likely if the slope is steep and/or the snow is hard.
Medium Exposure (E2): As well as the slope itself, there are some obstacles (such as rock outcrops) which could aggravate injury.
High Exposure (E3): In case of a fall, death is highly likely.
Extreme Exposure (E4): In case of a fall, the skier faces certain death.
A classic couloir; steep, straight and narrow, facing south-west.
In addition to the technical difficulties of the couloir itself, the approach is complex, through serious terrain and requires good route-finding skills.
From the Dôme des Petites Rousses follow the Les Perrins North route until the steep traverse above the Perrins bowl.
Instead of turning right into the bowl, pop over the ridge on your left to gain the Plateau de La Plate.
Keep right below the rocks, until the couloir starts to appear at the far right of the plateau, with a short rock-face bounding it on the right.
Ski the couloir direct, and from the exit slopes cross flattish ground to reach the Les Rousses piste.