Aiguille de Bionnassay Traverse


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2-4 days

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1 climber per guide

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Combine with:
Mont Blanc Traverse
Dômes de Miage

The North Face of The Aiguille du Bionnassay

With so much attention given to the peaks close to Chamonix, the large outlying peaks to the west of Mont Blanc are too often neglected. The Dômes de Miage and the Aiguille de Bionnassay offer very fine ice and snow routes, some on the airy crests and others on the north faces.

The traverse of the Bionnassay is a classic snow arete, very narrow, with a purity of line that is perhaps unequalled in the Alps. If ever there was a snow climb that one would call "exposed", this is it. This route is comparable to the Traverse of the Liskam summits near Monte Rosa, but perhaps a bit longer and with more rock climbing in the lower sections. Even getting to the remote Durier hut, from which we start our climb of the Bionnassay, is a route in itself.

The crest of the Bionnassay is a wild place. The steep and long north face of the peak, under our left foot, drops 4000 feet to the Glacier de Bionnassay. To our right is another steep drop to the to the remote Glacier de Bionnassay Italien.

The climb acn perhaps best be described as a long traverse, first over the Bionnassay then up the connecting ridge to the Dômes du Goûter. The route can be lengthened at both ends, starting with a Traverse of the Dômes de Miage, then the Bionnassay, and finishing with a climb of Mont Blanc, and on to the Aiguille du Midi via the Traverse of Mont Blanc. This combination gives us a four-day program of fine high altitude climbing.

But even if your climb will culminate at the Dôme de Goûter, the best way to approach the Aiguille du Bionnassay is via the Dômes de Miage. With this three day itinerary, we would first climb to the Conscrits hut. The following day we traverse the Dômes and continue on to the Durier hut. On our last day we would climb up and over the Aiguille du Bionnassay, then up to the Dôme d Goûter on Mont Blanc's normal route and descend this last to the Nid d'Aigle and the cog railway into the valley.

Climbing on the Bionnassay
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The summit ridge fo the Bionnassay


The climb of the Bionnassay includes both rock and ice climbing. The rock is not particularly difficult, perhaps mid-class 5 (French 4b), but it is often climbed in the cold of early dawn, and often crampons are worn on the snowy rock. But for most climbers the crux of the route is the very narrow crest, where careful crampon work is required as well as a cool head. Here, the climbing is not difficult but the great exposure and the climbing right on the narrow crest requires confidence and skill. Good conditions are required on this peak, if conditions are too icy it is not advised.


This is a route of skilled mountaineers who have had significant experience on comparable very narrow snow ridges. Good cramponing skill is require as well as a very high level of fitness.


This climb combines very well with a traverse of the Dômes de Miage, which can be used as an "approach" to the Durier hut. Additionally, we can add another day to the itinerary, include a stop at the Goûter hut, then continue up Mont Blanc, descending the Traverse to the Aiguille du Midi and the cable car back to Chamonix.

Climbing on the Dômes de Miage, Bionnassay behind
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The Aiguille du Bionnassay from the Dôme du Goûter
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Kathy Cosley & Mark Houston
UIAGM Internationally Licensed Mountain Guides

AMGA Certified • SNGM members
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