The traverse of the Pointes Lachenal is a very good, short route that can be done in half a day. Allthough it is a short route on a small, apparently insignificant summit. It is a good acclimatisation route and a good introduction into classic Chamonix mixed terrain. If the route is too short for you, you can climb the Cosmiques ridge on the Aiguille du Midi on the same day.
From Chamonix, the approach is very straightforward. Take the Aiguille du Midi cable car. Descend the summitridge to the Vallée Blanche and the Col du Midi. You can see the Pointes Lachenal on the left of the Triangle du Tacul. Go to the eastern summit. The route starts on the wide snow slope.
From the Refuge des Cosmiques, cross the Vallée Blanche and go to the eastern summit.
Gain the eastern summit via it's snow slope(45°). Follow the ridge towards the second summit and move to the south side. Rappel 10m to a snowy col(belay in situ). Climb a chimney for 45m (Loose rock)(4a/5.6) and continue to the third summit.
Descend towards the col (danger of serac fall) and go back to the Col du Midi.
Glacier gear, rope, helmet, a few cams
Topo: Snow, ice and mixed Vol 2, François Damiliano
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