Brèche Puiseux : Traverse via Glacier des Périades

From the top of the Aiguille du Midi tram, traverse a system of concrete tunnels to reach the beginning of a well marked ridge (small party ledge at the start). Descend it for 200 meters carrying your skis, crampons may be useful. The slope becomes less steep and broader (classic ski route start).

Descent via Vallée Blanche classic route: 2 hours. Descend a first slope for 100 meters (east) then go diagonally towards the south to pass to the west of spot elevation 3550 over not very steep slopes. First follow these slopes towards Col du Midi then go diagonally towards the east to reach the base of the rocks resulting from spot elevation 3541 (western end of Gros Rognon). Descend to the South via gentle slopes towards the base of Pyramide du Tacul. Go diagonally towards the east, pass under the Vallée Blanche gondola then head towards La Bédière (north) around 3000 meters. You reach the lower base of the Petit Rognon, the slope becomes steeper and crevassed. Stay well to the left of Séracs du Géant.

Traverse to the north towards Requin refuge while remaining on the left bank of the glacier (crevassed section and exposed to serac falls). Pass under Requin refuge to reach "la Salle à Manger". Around 2450, traverse Tacul glacier towards the east to reach its right bank.

Climb to Brêche Puiseux: 5 hours. At the end of the traverse of Salle à Manger, put your skins on and go up Périades glacier via its right bank (crevasses in places, sequence exposed to the serac falls coming from Dent du Géant). Go up this glacier in the same part until the rocks located around 3000 meters, south of Pointe Sisyphe. Pass between this point and these rocks then go diagonally towards the south then towards the east to reach the base of the corridor climbing to the Brêche Puiseux. Go up this corridor (45° for 250 meters) until the Brêche.

Descent from Brêche Puiseux: 3 to 4 hours until Chamonix. Descent begins with a rappel down to the W side of the Mont Mallet glacier. How long each rappel is depends on (a) how deep the snowpack is below; (b) which top anchor you choose; (c) what quality of intermediate anchors you're willing to accept. Using a top anchor at the Breche itself, in a low snow year it might be 50 vertical meters down over mostly loose rock to reach the snow below - (see the French-language description here on c2c; also see the other modern popular French-language ski website which is not c2c). In the old days sometimes in a big snow year there was no rappel required at all. But recently it's not unusual for it to be 40 meters or more. If you can somehow find a trustworthy intermediate anchor in the midst of the loose rock, could perhaps split it into two 25-meter rappels - (see the Italian-language description here on c2c).
There is another top rappel anchor by the Bivouac des Périades, an old wooden box about 2 meters wide, which can be reached by climbing the ridge NorthWest above from the Breche (with a couple of thoughtful exposed moves). The rock is generally more sound below this top anchor, the top anchor is very securely designed, especially if you bring a "cows tail" or leash with an extra carabiner for clipping to the anchor while setting up to rappel. There is an intermediate anchor in the south rock wall of the gully. It is rumored that this gully can be descended with two 25-meter rappels. Might still be some steep snow to boot down after the second rappel.
It is recommended to read recent reports on various websites before deciding how many ropes to bring and how short or long each rope needs to be.

Next descend on the Mont Mallet glacier. The descent is carried out by following the left bank of this glacier (crevasses, steep sequences), sometimes on the glacier, sometimes on its left bank. You then reach unrelenting and uniform slopes where the snow remains generally good rather long after a snow fall. The normal lowest section to reach Leschaux glacier is by a corridor with a section at least 35° (but perhaps this could be avoided by going farther east). Follow the glacier until reaching Mer de Glace and the Vallée Blanche route. Follow it via easy slopes until the level of the gondola which goes up to the Montenvers rail station.

To descend to Chamonix there are two solutions: - Via the gondola and the Montenvers train, - on skis (1h15) if snow conditions permit it. Follow the glacier in its centre until around 1700 meters. Then approach its left bank (steep sequence) to leave it around 1600 meters. Then you need to take off your skis and carry them for 15 minutes (increase of 50 meters) to reach Cabane des Mottets (located at spot elevation 1638). Then follow the trail called "Sortie Vallée Blanche" on the map until Chamonix.

Variant: From Brèche Puiseux it is possible to reach Mont Mallet glacier and descend from Mont Mallet glacier skirting the north face of Grandes Jorasses.

It is also possible to first do another tour in the upper section of the Mer de Glace (e.g. Col d'Entreves, Cirque Maudit, Tour Ronde, Petit Flambeau, Pointe Helbronner / Rifugio Torino) then descend the normal Vallee Blanche route to sleep at the Refuge du Requin, then make a much earlier start up the Périades glacier to ascend to the Breche. Useful for slower parties, or on popular days when it might be more difficult to get a place on the early lift rides up to the Aiguille du Midi.

Périades glacier - the slope of the upper two-thirds of the ascent is fairly sustained -- do not expect to find any gentler "resting spots". The couloir or corridor finishing at the Breche is not visible from any point on this ascent (but can be seen much earlier in this tour from near the Aiguille du Midi if know where to look).

Steep slope in the climb towards the Brêche Puiseux (250 meters at 45°). Since the couloir is partly sheltered from many typical wind directions, the snow in the corridor/couloir is often less packed by the wind than the surface of the Périades glacier. Since this tour is popular, often there will be other parties climbing above you in the steep couloir, perhaps inadvertently sending debris on you.

The descent of Mallet glacier is crevassed.

To descend until Chamonix on skis, the beginning of season (January, February) is better

Access:
Blanche Chamonix motorway. Aiguille du Midi tram at the entrance to Chamonix. Return to Chamonix on skis or by the Montenvers train

Accommodation:
The Aiguille du Midi tram is often very crowded. You can book a seat for the ascent at 08.92.68.00 67. It is possible to do this route in two days and sleep at the Requin refuge (04.50.53.16.96).

Glacier equipment (ice axe, a pair of crampons at least for the group, rope, safety equipment) is indispensable.
Helmet if concerned about other parties climbing above you in the steep couloir.
GPS and navigation instruments in the event of overcast weather.