Rockfax Description
III, 500m, 6 - 10 hours. A true alpine classic, the Charmoz-Grépon Traverse remains one of the best mountain journeys in the Alps. The retreat and disintegration of the Nantillons Glacier has made the descent more dangerous than it used to be so think carefully before attempting this line. Get it right and you will be rewarded with a stunning journey through some magnificent rock architecture.
Approach - From the Plan de l'Aiguille, take the path to Lac Bleu then follow a vague track climbing eastwards, directly towards the Petits Charmoz. Cross the moraine beneath the Glacier de Blaitière following the line of least resistance (occasional cairn) to reach the ridge coming down from the Aiguille de Blaitière Northwest Ridge. Cross the next bowl (more boulders but easier than the Blaitière moraine) in the direction of the Charmoz to reach the ridge overlooking the foot of the Nantillons Glacier. If you are going straight to the routes from the lift or the Plan de l'Aiguille hut, continue across the glacier, but if you are planning to bivi, walk up a good path along the ridge which leads to some superb bivi spots at the foot of the northwest ridge of the Blaitiére. The glacier is extremely prone to rockfall and, although it can be crossed high up, it is usually worth the extra effort of descending slightly and crossing level with the southwest ridge of the Aiguille de l'M - whichever way you cross, don't dawdle.
Walk up to the foot of the Rognon des Nantillons and scramble this via broken rock to reach the upper part of the Nantillons Glacier. Climb up the glacier and then cross it towards the start of the Charmoz-Grépon Couloir. Much of the approach above the Rognon is serac threatened so move quickly.
1) Climb the couloir (40 degrees) for 200m then move left out of it onto some large terraces marked with cairns.
2) 3c. Cross the terraces up and leftwards to reach the foot of a long corner and chimney system. Climb this, mostly scrambling terrain with the odd short section of thuggish granite climbing, to reach the Charmoz summit ridge. The most famous section of the chimney system is the offwidth Burgener Crack, which will feel pretty stiff to those not used to the intricacies of granite thrutching!
3) 4c. Follow the ridge crest and go around the first small tower on the right (4c) before dropping onto the left of the ridge. From here, follow the left of the ridge via the odd technical step (4c) and short downclimb (possible to abseil) to reach the Charmoz summit from the left side of the ridge. Abseil back to the foot of the summit tower and follow easy but sometimes loose rock to reach the top of the Charmoz-Grépon Couloir.
4) 6b. At the top of the couloir, don't descend to the lowest point but instead climb a short corner (4c) on the right of the ridge and then traverse over onto the left of the ridge. Follow a ledge left for 20m. At the end of the ledge, climb up to a gap then go down and left before crossing a slab (4c) to reach the Mummery Crack 10m below its top. The Mummery was originally graded 5b, but most teams agree that it is way harder in modern money. Climb it to reach the ridge crest again.
5) Move back left of the ridge and then climb a crack to reach a 'letter box'. Go through this and onto the right of the ridge.
6) 4c. Follow the ridge crest via some superb flakes (4c) to reach an abseil point. Make a short abseil to a small gap in the ridge. Scramble up the small pinnacle opposite and then make another short abseil onto the right of the ridge. Follow a narrow ledge along before crossing back onto the left of the ridge and continuing along another ledge to a Z-shaped crack. Climb this to the Grépon summit. Give the summit Madonna a peck!
7) Make a 20m abseil onto the left of the ridge then move onto the right and descend (mainly downclimbing, with the odd short abseil) a series of ledges and chimneys to a shoulder. From here it is possible to scramble down to the Col des Nantillons, but a better and safer option is to use the recently installed line of bolted abseils (2 x 50m ropes required) to descend the Grépon's west face.
Descent - Walk down the Nantillons Glacier. Shortly after passing the bottom of the gully at the start of the route, go left to pass under the serac (move quickly on this section) and then descend to the Rognon des Nantillons (the rock buttress which splits the glacier). In August 2014, a new line of bolted abseil anchors was installed here to avoid the more exposed descents down the lower section of the glacier. There are six abseils, all a maximum of 25m, which lead onto the traverse across the lower glacier. This final traverse is threatened by rockfall, so don't stop for a breather until back on the moraine ridge that overlooks the glacier. © Rockfax

Ticklists: Rebuffat's 100 Finest Routes in the Mont Blanc Massif, ROCKFAX Chamonix: Top 50.

Hidden 04/Aug/16 AltLd dnf
Hidden 12/Aug/15 AltLd dnf
mike mo ??/2014 -
jcw ??/2013 -
tsl42 ?/Jul/11 2nd dnf

Think this is what we tried to do. Doesn't matter too much as didn't manage it due to a little bit too much of a leisurely start and my inability on cracks.

JonHarvey ?/Aug/08 AltLd O/S
Hidden ?/Aug/08 AltLd O/S
Hidden 18/Aug/07 AltLd
alpinist63 22/Aug/01 -
Hidden 10/Aug/00 AltLd
tompercy 28/Jul/95 -

Continued onto Aig des Grands Charmoz

with Tim Loftus, Tom Bridgeland
andy_pemberton ?/Jul/95 -

Part of Charmoz - Grepon Traverse (I think!). Great route. We bivvied behind a flake of rock just above the bergschrund and left bivvi gear and big boots there then diagonally absailed and crawled inside the bergschrund to get back to it!

with Jon Scorer
Hidden ?/Aug/92 -
Tim Sparrow ?/Aug/92 -
with Chris D
Lone Rider ??/1986 AltLd
Hidden ?/Aug/81 -
Hidden 18/Aug/80 AltLd
Chris Craggs ??/1980 -
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