Lac Fer

Lac Fer is a high-altitude lake in the commune of Saint-Étienne-de-Tinée, in the Alpes-Maritimes department, within the boundaries of Mercantour National Park. It sits at 2,541 metres above sea level in the Haute-Tinée valley, tucked into the side valley of Malignas at the foot of the western face of Mont Ténibre. The lake fills a rocky cirque with a roughly circular outline and covers about 4.27 hectares. Its turquoise water, a trait shared by several high lakes in this part of the Mercantour, makes it a favourite subject for hikers carrying a camera.

How do you get to Lac Fer?

Most visitors set out from Saint-Étienne-de-Tinée, roughly 7 km from the lake by trail. The walk itself typically takes between 2 hours 15 minutes and 2 hours 45 minutes one way, depending on fitness and pace. Part of the approach follows the Chemin de l'Énergie, a former service track built to support hydroelectric works high in the valley. After a tunnel collapse in 2016, a permanent detour was put in place between Plan de Ténibre and the Lac Pétrus area, continuing on toward Lac Fer. The detour is clearly signposted and runs along an upgraded path, so it adds no real technical difficulty for hikers used to mountain trails.

What should you know about the lake itself?

Lac Fer is one of several lakes scattered across the upper reaches of the Haute-Tinée valley, below the Ténibre massif. Compared with its neighbours it is considered fairly deep and sizeable. The local fishing association, AAPPMA Haute Tinée, stocks the lake with fish, and by some accounts Lac Fer receives heavier restocking than a few of the surrounding lakes — which makes it a draw for anglers, provided they hold the required permit. Weather above 2,500 metres can turn quickly: a clear morning can give way to fast-moving cloud and a sharp drop in temperature within the hour, so an early start and a close eye on the sky are standard advice from regulars.

What routes pass near Lac Fer?

The lake is a waypoint on longer, multi-day loops through the Mercantour. A well-known three-day itinerary out of Saint-Étienne-de-Tinée links Lac Pétrus, Lac Fer, Lac des Babarottes and the Lacs de Vens, and more ambitious hikers extend it with a climb to the nearby Aiguilles de Tortisse (2,672 m). For a single-day outing, Lac Fer also works well as a destination in its own right, with a return by the same path. Anyone planning the route should check the IGN Haute Tinée 1 map (3639 OT), which marks the Chemin de l'Énergie and the landmarks around Plan de Ténibre.

FAQ

How high up is Lac Fer? The lake lies at 2,541 metres, in a rocky cirque below the western face of Mont Ténibre.

How long does it take to reach the lake? From Saint-Étienne-de-Tinée, allow between 2 hours 15 minutes and 2 hours 45 minutes one way, over roughly 7 km.

Can you fish at Lac Fer? Yes. The lake is stocked by the local angling association, AAPPMA Haute Tinée, though fishing requires the permit valid within Mercantour National Park.

Is the trail technically demanding? It's a typical high-mountain trail with substantial elevation gain but no climbing sections — good fitness and proper footwear are enough. One stretch follows a detour set up on the Chemin de l'Énergie after a tunnel collapse in 2016.

Can Lac Fer be combined with other lakes in one trip? Yes — it sits on a popular loop that also takes in Lac Pétrus, Lac des Babarottes and the Lacs de Vens, often walked as a two- or three-day trip with an overnight in the mountains or at a nearby refuge.