West Ridge

The North Ridge is the classic and best-known route on Aiguille de Bionnassay. It is a serious alpine ridge climb with sustained mixed terrain, exposed sections, and objective hazards from snow and ice conditions. The route is typically climbed in stable weather and good early-season or firm conditions. It demands competent movement on steep snow, rock, and occasional ice, plus comfort with exposure on a narrow ridge. Because of the mountain’s glaciated setting, crevasse and serac hazards can affect the approach. This is a full mountaineering objective rather than a hiking route.

This is the well-known traverse linking Aiguille de Bionnassay with the Mont Blanc summit route. It is a long, committing alpine traverse with sustained exposure and significant objective hazards. The connecting ridge is narrow and often corniced, and conditions can vary greatly with wind and snow loading. It is usually undertaken by strong parties with solid ridge technique and efficient ropework. The traverse is more of a major mountaineering itinerary than a single short climb. It is documented in major Mont Blanc Massif guidebooks as a classic high-level link-up.