Lac Blanc variant

The most famous detour on the TMB: Lac Blanc, a mirror for the Mont Blanc massif, in the heart of the Aiguilles Rouges reserve.

≈ 3 km 1.9 mi≈ 250 m 820 ft ascent≈ 250 m 820 ft descent1h30 – 1h45Lac Blanc 2,352 m 7,717 ftModerate

Lac Blanc variant — Photo: Tiia Monto · CC BY-SA 3.0

Description

From the Tête aux Vents, the main route heads straight for La Flégère. The variant instead climbs to the Chéserys lakes and then to Lac Blanc (2,352 m), in a setting of rock slabs and small high-altitude lakes.

On a calm day, the Aiguille Verte, the Drus, the Grandes Jorasses and Mont Blanc are reflected in the water: it is one of the iconic images of the tour. The Refuge du Lac Blanc, on the lakeshore, lets you experience sunset and sunrise over the massif.

The descent to La Flégère follows a rocky and very busy path. Allow about 1 hr 30 min more than the direct route.

Tips

Set off early: the lake is very busy during the day in July and August.
The Refuge du Lac Blanc is small: book as soon as reservations open.
To avoid the ladders, climb up to Lac Blanc from the Col des Montets via the Chéserys lakes.
Chamonix town council is considering compulsory booking with a daily cap at Lac Blanc from summer 2027: check before you go.