Aiguille de Bionnassay
4,052 m
France, Italy
Also known as Эгюий-де-БьоннасеAlso known as
Эгюий-де-Бьоннасе
- Elevation
- 4,052 m
- Prominence
- 164 m
- Difficulty
- 6/10
- Alpine climb
- Best Season
- Jun–Jul
- Routes
- 2
Hut closedReported 25 Aug 2026
The Tête Rousse and Goûter huts (north-west face approach and Goûter descent) were closed by municipal order in August 2026 because of rockfall in the Grand Couloir and reopened on 26 August 2026 (order ARR2026_015 SECU).
montblanc.ffcam.frAdvisoryReported 19 Jul 2025
Two French climbers reported missing on 18 July 2025 were found dead by the Chamonix PGHM at the foot of a ridge of the Aiguille de Bionnassay; they are thought to have fallen from the ridge.
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Routes
2Sources differ: PD+ (Wikipedia; Guide Vallot 1987 (PD, per Camptocamp)) · French 3b (Camptocamp)
The easiest way up: from La Gruvaz or Bellevue to the Plan Glacier hut, across the Miage glacier and up a cabled spur to the tiny Durier hut on the Col de Miage (3,358 m), then a short, varied ridge of rock (II–3b) and snow to the knife-edge summit. Often continued along the east ridge to the Dôme du Goûter and Mont Blanc.
Elevation Profile
- Distance
- 11.3 km
- one way
- Ascent
- +3,052 m
- −111 m lost on the way up
- High Point
- 4,052 m
- Time Up
- 11h 48m
- DIN 33466
- Time Down
- 7h 53m
- DIN 33466 · same way back
Day one: from the car park at La Gruvaz (about 1,090 m) above Saint-Gervais, walk or take a 4×4 taxi up the track to the Chalets de Miage (1,550 m), then follow the marked path, with handrails in places, to the Refuge de Plan Glacier (about 2,700 m); alternatively start from Bellevue (tramway or Les Houches cable car) via the Col du Tricot. From Plan Glacier a path with some cables descends south-east onto the Miage glacier (the small French one); cross it south-west to the foot of the rock spur below the Col de Miage (big red paint mark), right of an obvious gully, and climb the spur, cabled near the top, to the Refuge Durier (3,358 m). Staying on the spur keeps you out of the stonefall in the gully. Camptocamp gives about 3 hours to Plan Glacier and 6 hours to Durier from the valley. Summit day: from the hut cross a first rock band rightwards (cairns) onto the south ridge, follow snow or a path to an easy, narrow rock crest (II), then a horizontal snow ridge to the foot of a rock bastion. Climb it directly or by ledges and steps on the right to a big corner with chained belays; one athletic move leads to the crest, and ledges on the Italian side turn the end of the rock. A final snow slope (up to about 50°) leads to the exposed summit. Allow 2½–3 hours from the hut. Descend the same way, down-climbing or making three 25–30 m abseils from the chained belays to the snow below the bastion (beware if it is icy), then back to Durier and down to the valley; the return is long. Many parties instead traverse east along the narrow, often corniced frontier ridge to the Col de Bionnassay and the Piton des Italiens, then up to the Dôme du Goûter, the 'voie royale' to Mont Blanc.
Start
La Gruvaz1,111 m
- Tramway du Mont-Blanc or Bellevue cable car (Col du Tricot approach)
- Train to Saint-Gervais-les-Bains-Le Fayet, bus towards Les Contamines (stop near La Gruvaz; summer shuttle La Villette–La Gruvaz), or the Tramway du Mont-Blanc / Bellevue cable car to Bellevue for the Col du Tricot approach.
- Parking at the trailhead
Stages
| Day | Stage | km | m ascent | m descent | Time |
|---|---|---|---|---|---|
| 1 | La Gruvaz → Refuge Durier | 9.8 | 2,344 | 101 | 9h 14m |
| 2 | Refuge Durier → Aiguille de Bionnassay | 1.5 | 704 | 11 | 2h 33m |
Waypoints
- Parking: La Gruvaz1,111 m
- Hut: Refuge de Plan Glacier2,696 m
- Hut: Refuge Durier3,359 m
- Summit: Aiguille de Bionnassay4,052 m
Key Passages
- Cabled spur to the Col de Miage (stonefall in the adjacent gully)
- Narrow rock crest (II) and snow ridge on the south ridge
- Rock bastion with chained belays and one athletic move
- Final snow slope (up to 50°) and exposed summit crest
Equipment
0/11 packedDownloads
Route confidence 80%Overview
A 4,052 m satellite of Mont Blanc on the French–Italian border above Saint-Gervais, famous for its knife-edge snow summit and corniced east ridge. Every route is a serious snow and ice climb; the easiest, the south ridge from the tiny Durier hut, is graded about AD.
The Aiguille de Bionnassay stands at the western end of the Mont Blanc summit chain, linked to the Dôme du Goûter by a long, narrow frontier ridge. From the Chamonix and Saint-Gervais side it shows a 1,000 m glaciated north-west face above the Bionnassay glacier; to the south and west it drops to the small French Miage glacier and the Italian Bionnassay and Miage glaciers. Its summit is a sharp crest of snow and ice, and with about 164 m of prominence it is one of the most distinctive subsidiary peaks of Mont Blanc.
The usual way up is the south ridge from the Refuge Durier on the Col de Miage, reached in a day from La Gruvaz or Bellevue via the Plan Glacier hut: a short mixed ridge with rock to II–3b and a final 50° snow slope. The north-west face from the Tête Rousse hut is the classic snow and ice route. Many parties combine the south ridge with the airy east ridge to the Dôme du Goûter as the start of a traverse to Mont Blanc.
Expect exposure throughout, cornices on the east ridge, stonefall below the Col de Miage and crevasses on every approach. In July 2025 two climbers died after an apparent fall from one of its ridges.
Climbing Notes
You need to be comfortable cramponing on exposed 45–50° snow and narrow ridges, climbing grade II–III rock in boots, abseiling and handling crevassed glaciers. Acclimatisation matters, especially if continuing to Mont Blanc. Hiring a guide is common for the traverse.
Typical itinerary: day 1 from La Gruvaz (or Bellevue via the Col du Tricot) to the Plan Glacier hut, or straight on to the Durier hut (about 6 hours); day 2 a 03:00 start for the south ridge (2½–3 hours), then either back to Durier and down to the valley, or along the east ridge to the Dôme du Goûter and down the Goûter route (which needs a Goûter-route hut booking) or on to Mont Blanc. The Durier hut has only 12–20 places and is staffed only until late August in 2026; book early and carry food if going outside the staffed period.
History
Florence Crauford Grove, Edward Buxton and Reginald Macdonald with the guides Jean-Pierre Cachat and Michel Payot made the first ascent on 28 July 1865 by the north-west face, reaching the summit in a thunderstorm. The south ridge was first climbed on 13 July 1888 by Georg Gruber with Andreas Jaun and Kaspar Maurer; a month later, on 13 August 1888, Katharine Richardson with Émile Rey and Jean-Baptiste Bich made the second ascent and the first descent of the east ridge to the Dôme du Goûter. The first winter ascent was on 20 March 1929 (Armand Charlet, Roger Frison-Roche and companions). The Durier hut on the Col de Miage dates from 1899 and is the oldest hut still standing in the French Alps.
Season
Best Jun–Jul- January: Not advisable
- February: Not advisable
- March: Not advisable
- April: Possible
- May: Possible
- June: Best (best window)
- July: Best (best window)
- August: Good
- September: Possible
- October: Not advisable
- November: Not advisable
- December: Not advisable
- Jan
- Winter
- Feb
- Winter
- Mar
- Winter; rare ski ascents
- Apr
- Spring ski-mountaineering for experts (north-west face)
- May
- Snowy; huts mostly unstaffed
- Jun
- Durier and Plan Glacier staffed; good snow on ridges and face
- Jul
- Main season
- Aug
- Icier ridges and face, more stonefall; Durier staffed only to 24 August (2026)
- Sep
- Huts unstaffed; icy conditions
- Oct
- Early winter conditions
- Nov
- Winter
- Dec
- Winter
Access & Permits
- Permits
- Mont Blanc normal-route hut reservation (if descending via the Dôme du Goûter)Optional
Not needed for the south ridge or the north-west face themselves. Parties who traverse to the Dôme du Goûter and descend the Goûter route are subject to the Haute-Savoie prefectoral decree of 15 June 2020: a named reservation at a Goûter-route hut, carried with ID, is required beyond the Tête Rousse glacier.
montblanc.ffcam.fr
- Hut Booking
- Refuge Durier: with the warden, +33 6 89 53 25 10 (refugedurier.ffcam.fr). Refuge de Plan Glacier: info@planglacier.fr or by phone. Tête Rousse: online only via montblanc.ffcam.fr.
- Fees
- Overnight fees at the Plan Glacier, Durier or Tête Rousse huts
- 4×4 taxi from La Gruvaz to the Chalets de Miage (optional)
- Tramway du Mont-Blanc or Bellevue cable car tickets (Col du Tricot or Nid d'Aigle approaches)
- Rules
- The track from La Gruvaz to the Chalets de Miage is restricted for private vehicles (access times and 4×4 only)
- Refuge de Plan Glacier: reservation compulsory in the staffed season
- The Durier hut is threatened by thawing permafrost; a project led by the Club Alpin de Saint-Gervais aims to dismantle and rebuild it on stable ground nearby
- Getting There
Saint-Gervais-les-Bains; Les Contamines-Montjoie
Geneva (GVA)
- Train to Saint-Gervais-les-Bains-Le Fayet, then bus towards Les Contamines; summer shuttle from La Villette to La Gruvaz
- By car: from Saint-Gervais towards Les Contamines, turning off to the La Gruvaz car park (about 1,090 m)
- Tramway du Mont-Blanc from Le Fayet (2026 season from 13 June) or the Bellevue cable car from Les Houches, for the Col du Tricot or Nid d'Aigle approaches
Hazards
- Glacier
- Crevasses
- Exposure
- Cornices
- Rockfall
- Avalanche
- Altitude
- Weather
Huts & Shelters
3- 2,700 m
Refuge de Plan GlacierRefugeStaffedBooking required
18 beds · Staffed 12 June – 8 September 2026; unstaffed dormitory with blankets the rest of the year
- 3,167 m
Refuge de Tête RousseRefugeStaffedBooking required
Late May to early October; closed in August 2026 until 26 August
- 3,358 m
Refuge DurierRefugeStaffedBooking required
12 beds · Staffed early June to 24 August 2026; open unstaffed otherwise (pay afterwards)