From the Plan de l'Aiguille, follow the path leading towards the Grands Mulets hut. Cross a boulder field to reach the moraine leading up to the Tournier spur of the N face of the Aig du Midi. Follow the moraine to the snow slope below the Peigne.

Go up the left side of the snow slope for about 50m, (sometimes a detour to the right is necessary) and follow a path along a ledge to the left. Pass through two small gaps to reach the SW gully which is to the left of the ridge coming down from the tower 3009, (also called the Papillons gully because it comes down from the summit of the Papillons Arete at the point where this ridge ends against the main face of the Peigne.)

Route 5h

Go up easy ledges on the true left bank and then the true right bank of the gully. Leave the gully by a smooth crack on the right (next to an obvious boulder) which leads to a vague shelf. (15m, 3c). Climb a rock step and exit by a slab leading to a sloping ledge (15m - 3b - thread belay). Follow the ledge and exit to the left (3b) on an extension to the Papillons Arete. Continue along this airy ridge to the right, to reach a large ledge which is where the modern routes end. Follow the ledge, cairn, then go up the gully and ledges to the right leading directly to the Tower 3009m.

Bypass this on the right and go up a well marked gully. Follow a series of ledges along the face of the Peigne leading to a gap at 3043m on the right. (2-3h)

From the gap, there are two alternates to the summit:

Descend the ramp leading to where the Peigne gully splits into three and from here go up by short steep steps in the gully to a flat area : "salle à manger".
Climb the start of the SW ridge by its crest, a pitch of 35m (4b then a broad crack, 5b) Peg belay. Do not go up to a peg and cord directly above, (unless you want to climb the Lépiney crack). Climb down a few metres on the right and make a long, horizontal traverse before rising slightly to a large quartz ledge : "la salle à manger" (40m, pegs, 3b, with a move of 4b).

Follow the ledge to the right, towards the ESE ridge, but before you reach it and at the level of the Col du Peigne (3121m) go to an open chimney which goes up to the right, climb this (pegs, 4c) to exit onto the summit ridge at a little notch with a peg belay. (Many people at this point take the wrong chimney and leave material behind. 2 pegs and a yellow cord means you are in the wrong chimney. Take the one 10m before, which is well polished and much easier.)
Gain the top of the ridge by a 40m pitch (4b, pegs.) Follow the crest of the summit ridge, or to its right. Make a 4m abseil to reach a last notch before passing through a slot to reach the summit, (2h).

Descent

From the summit, abseil 30m on the Chamonix side to reach a large terrace. The Lépiney crack is visible on the left. Descend the SW ridge about 10m and go onto the side facing the Pèlerins to find a bolted abseil point. Two 30m abseils bring you to the "salle à manger".

Now descend by the same route. There are some 30m abseils set up from the Papillons Arete towards the Papillons gully, which avoids climbing down some of the steeper sections.