The Vallée Blanche above Chamonix has earned a reputation as one of the most famous ski descents on Earth. Depending on snow conditions and the route taken, the glacier run can stretch to around 12.5 miles (20 kilometers), making it widely regarded as the world’s longest lift accessed ski descent. In a new video, European ski instructor Marius Quast documents his first experience on the legendary route, showing both its breathtaking scenery and the serious hazards that come with skiing through high alpine terrain.
A Legendary Glacier Route
Unlike a traditional ski run, the Vallée Blanche is an unmarked glacier descent beneath the Mont Blanc massif. Skiers begin by riding the Aiguille du Midi cable car to roughly 12,605 feet (3,842 meters) before making their way onto the glacier below.
The descent can cover nearly 12.5 miles (20 kilometers) under favorable conditions, although the exact distance depends on snow coverage and where the route finishes. In many seasons, skiers return to Chamonix using the mountain railway, while exceptional snow years can allow the descent to continue farther into the valley.
A Long Descent With Real Consequences
Its remarkable length is only part of what makes the Vallée Blanche famous.
Quast stresses throughout the video that the route is not patrolled or groomed and crosses active glacier terrain with hidden crevasses and constantly changing conditions. He recommends skiing with an experienced guide, noting that serious accidents continue to occur on the route.
The adventure begins with one of the most intimidating entrances in skiing. After leaving the summit station, Quast and his group put on crampons, climbing harnesses, and avalanche safety equipment before carefully crossing a narrow snow ridge with steep exposure on both sides to reach the glacier.
Ancient Ice And A Changing Landscape
Once on skis, the group followed a moderate variation across the Mer de Glace, the largest glacier in France. Towering walls of blue ice and expansive snowfields make the Vallée Blanche one of the most spectacular ski descents anywhere in the Alps.
Quast also highlights the effects of climate change during the tour. Exposed mountainsides reveal how much the Mer de Glace has retreated over the past century, and a new cable car opened in 2024 to improve access between the glacier and the mountain railway as the ice continues to shrink.
By the end of the day, Quast’s group had skied 7.3 miles with more than 6,770 feet of vertical descent before returning to Chamonix by train. While conditions prevented the full 20 kilometer journey, his video shows why the Vallée Blanche remains one of skiing’s ultimate bucket list objectives and why it is widely considered the world’s longest lift accessed ski descent.
