Lac du Grand Méan

Lac du Grand Méan is a high-altitude glacial lake sitting at roughly 2876 metres above sea level, inside Vanoise National Park, in the commune of Bonneval-sur-Arc (Savoie). It lies in the Graian Alps, right at the snout of the glacier that shares its name, tucked into a side branch of the valley known as the Cirque des Évettes.

How did this lake form?

The lake sits directly beneath the Grand Méan glacier, whose front ends in a steep wall of ice that drops straight into the water. During the warmer months, chunks break away from the glacier front and drift across the surface like small icebergs - a sight that few glacial lakes reachable on foot in the French Alps can match. The setting is stark and mineral, ringed by summits over 3000 metres, well above the treeline.

How do you get there?

The hike starts at the hamlet of l'Écot, about 4 km beyond the village of Bonneval-sur-Arc, at an elevation of roughly 2000-2027 metres - already inside Vanoise National Park. From there a marked path climbs the valley, crosses a bridge known as the Pont Saint-Clair (or Pont Romain), and enters the rocky terrain of the Cirque des Évettes, where the final stretch runs over loosely marked rock slabs. The round trip covers about 14 km with 950-1000 metres of elevation gain, translating into roughly 6-7 hours of walking. It's rated a demanding outing that calls for sturdy trekking boots, solid fitness, and confident footing on rock in places.

Where can you stay along the way?

At about 2594 metres, the trail passes the Refuge des Évettes, a hut with an unusual backstory. Built in 1969-1970 to a design by architect Guy Rey-Millet, it used a lightweight metal structure developed with engineer Jean Prouvé and Léon Petroff. The prefabricated components were flown in by helicopter, letting the whole hut go up in a single season. It's now regarded as a notable piece of 20th-century mountain architecture. Staying overnight here lets hikers split the walk over two days and reach the lake early in the morning, when the light on the ice is at its best.

When is the best time to go?

July through September is the ideal window. Earlier in the season, snow can still cover the rock slabs above the bridge, making footing unreliable and the route harder to follow.

Frequently asked questions

How high up is Lac du Grand Méan? The lake sits at about 2876 metres above sea level, right at the foot of the Grand Méan glacier.

Where does the trail to the lake start? At the hamlet of l'Écot, about 4 km from Bonneval-sur-Arc, at roughly 2000 metres.

How long does the hike take? The round trip is about 14 km with 950-1000 metres of elevation gain, usually 6-7 hours.

Is there anywhere to stay overnight on the route? Yes, the Refuge des Évettes at about 2594 metres, a hut built with components designed by Jean Prouvé.

Is the trail difficult? Yes, it demands good fitness and solid boots - the last section crosses loosely marked rock slabs.