Lac de Belledonne

Lac de Belledonne is a mountain lake in the commune of Allemond, tucked into the Eau d'Olle valley at the foot of the Grand Pic de Belledonne, on the southern flank of the Belledonne range in the Isère department of the French Alps. Sitting at roughly 2,160–2,170 metres above sea level, it covers a modest surface of under two hectares, making it a compact but strikingly scenic destination in this part of the Alps.

Where is Lac de Belledonne located?

The lake sits within the Belledonne massif, a mountain chain stretching around 60 km between the Isère and Romanche valleys and 10 to 15 km wide. Its highest point, the Grande Lance de Domène, reaches 2,977 metres, and the range counts more than 50 summits above 2,500 metres. The massif is built mainly of crystalline rock — granite, gneiss and schist — giving the landscape a rugged, mineral character offset by spruce forest and alpine pasture lower down.

How do you reach the lake?

The usual starting point is the car park at Coteyssard, above Allemond, reached via the local road known as La Traverse, with parking near the Dreyta stream at about 1,275 metres. The round-trip hike covers roughly 11 km with about 916 metres of elevation gain, putting it in the "difficult" category. Walkers typically need around 4 hours there and back.

The trail climbs through distinct bands of vegetation: forest first, then a stop near the Cabane du Chazeau hut, followed by mountain pasture, and finally a stretch of scree with a purely mineral feel just before the lake itself.

What can you see around the lake?

The setting is wild and dramatic — the lake lies in the shadow of surrounding peaks, with views toward the Croix de Belledonne ridge and, across the valley, the Grandes Rousses and Rissiou massifs. That contrast between bare rock at altitude and the still water below is what draws hikers looking for a quieter alternative to the busier lakes elsewhere in the French Alps.

When is the best time to visit?

Spring is generally considered the best season, when patches of snow still linger around the shoreline and add to the scenery. Because of its altitude, the lake can remain partly frozen well into early summer, so it is worth checking current snow conditions before setting out, particularly in May and June.

FAQ

Is Lac de Belledonne the same lake as Lac de la Sagne in Allemond? No. Both lie within the same commune of Allemond, but they are separate lakes with different locations and character — they should not be confused with one another.

How long does the hike to the lake take? The full round trip typically takes about 4 hours, covering roughly 11 km with around 916 metres of elevation gain.

Is the trail suitable for beginners? The route is rated difficult due to its length, elevation gain, and the final scree section, so prior mountain hiking experience is recommended.

Where's the best place to start the hike? The standard starting point is the car park at Coteyssard above Allemond, reached via the La Traverse road, with additional parking near the Dreyta stream at about 1,275 metres.

Does the lake freeze? Given its altitude, the surface can stay partly covered in snow and ice into early summer.