Arête E, voie Allain

Approach

From the Envers hut, go to the bergschrund at the foot of the Ryan ridge on the Plan, cross it, (usually best to the left of the spur under the N face of Pain de Sucre) and climb up the bottom of the Ryan until you reach the Plan-Crocodile couloir. Cross it as low as possible, (ledge plus easy angled slabs, stonefall risk.)

Route

Initial section

Climb the first part of the Crocodile ridge by keeping near to the gully, (but far enough away to avoid stone fall) by as series of ledges and little steep rock walls. Then climb to the right to the crest above the first steep step of the ridge. (Be careful not to traverse too low down, you need to be above the level of the shoulder of the Ryan before going to the right.) An area of terraces leads to the foot of a nice crack (4b) which gives access to the crest of the spur. From here you can see an obvious corner on the right side of the pillar (towards Caiman) where the difficulties start.

The climb

L#1 | A crack leads to the foot of the corner, (40m, 4c) L#2-3 | In the corner, a smooth chimney crack, overhanging in places., difficult jamming and committing, (some old pegs, one can place some friends but not everywhere.) Nearer 5c than 5b (topo) for P2, 25m to the niche,) and 6a (P3, 20m + 25m easier climbing on some flakes.) Hauling the sacks recommended.
L#4 | Climb a corner, (5b) at the side of a pillar until slab which is passed using pegs, (ascending traverse from left to right, 4 pegs at A0, 1 foot sling useful to exit,) easier than the corner, then on the crest until the foot of the next corner (45m). L#5 | Another nice corner, vertical with a crack at the back, not much for the feet, gives good, technical climbing, (10m, 1 peg at the start, 5c). Follow the crest until an inclined slab, (1 move of 5b to finish.)
L#6 | From the belay at the top of the slab, go down to its left hand end and start a leftward traverse beside a slanting crack in an orange, vertical wall. It is very impressive, exposed, but not too difficult, (still 5b rather than 4c, 20m. 1 peg at the start.) L#7 | By some ledges and terraces, reach a nice 30m crack to the left, (4c, 45m). Belay at the foot of a little corner. L#8 | Nice layback in the corner, strenuous but straight forward (4c/5a) then some short, vertical walls to the foot of the last step. L#9 | To the left of the crest, a nice corner bristling with pegs, climbed by jamming and strenuous bridging (20m, a good 6a, there is an easier alternative further to the right,) leads to within 5m of the summit.

Descent

Follow the summit ridge for 20m towards the Plan. A 45m abseil, (ring in place,) leads to the Crocodile-Plan gap. Get back onto the ridge then the snow/ice slopes to the right to go around the summit of the Plan. Descend the easy snow ridge to the Col Supérieur du Plan. From here either descend to the Requin hut by the Envers du Plan glacier, (very crevassed) or continue along the ridge to the Aiguille du Midi, (very long.)