Lac de Fenestre

Lac de Fenestre is a small high-altitude lake tucked into Mercantour National Park, within the commune of Saint-Martin-Vésubie in the Alpes-Maritimes department of southeastern France. Sitting at roughly 2,260 metres, it lies in the upper Vésubie valley, close to the Italian border, surrounded by the bare rock and sparse vegetation typical of this high mountain massif.

Where does the trail to the lake start?

Access to Lac de Fenestre begins at the Madone de Fenestre refuge and sanctuary, at 1,903 metres, reached by a mountain road roughly 12 kilometres from the village of Saint-Martin-Vésubie. Beyond its role as a trailhead, Madone de Fenestre is itself a notable Marian shrine: a Benedictine chapel is recorded here as early as the 9th century, later rebuilt by the Templars in the 13th century and restored again in the 14th century after the order's suppression. Every year, on the last Saturday of May, a procession carries the statue of the Virgin on foot from Saint-Martin-Vésubie back to the sanctuary.

What does the hike to the lake look like?

From the refuge, the GR52A long-distance trail leads up to the lake. The climb to Lac de Fenestre itself is rated easy, with no technical difficulty: about 360–370 metres of elevation gain, and a round trip of roughly 1 hour 45 minutes. That makes it one of the more approachable alpine lakes in the Mercantour, open to hikers without mountaineering experience.

Is it worth continuing to Col de Fenestre?

Hikers with more time can push on to Col de Fenestre, a pass at 2,474 metres marking the border between France and Italy. Combining the lake and the pass makes for a full outing of about 7 kilometres and 3 hours, with a total elevation gain close to 570 metres. Remnants of old border fortifications still stand at the col, a reminder of how strategically important this crossing once was, and the pass opens onto views of the Italian Piedmont side of the range.

Towering above the whole basin is the Cime du Gélas, at 3,143 metres the highest summit in the Alpes-Maritimes department, visible from the shores of the lake and a popular objective for more experienced mountaineers.

What wildlife might you see along the way?

Mercantour National Park holds a large population of chamois and ibex, and both are commonly spotted around Madone de Fenestre without needing to venture far off the main path. It's one of the reasons the Vésubie valley and the Lac de Fenestre area draw both casual walkers and hikers planning longer high-mountain routes.

FAQ

How high up is Lac de Fenestre? The lake sits at approximately 2,260 metres above sea level, inside Mercantour National Park.

Where do you start the hike? At the Madone de Fenestre refuge (1,903 m), reached by road from Saint-Martin-Vésubie.

How long does it take to reach the lake? About 1 hour 45 minutes round trip, with 360–370 metres of elevation gain.

Is the pass beyond the lake worth the extra effort? Yes — Col de Fenestre (2,474 m) sits on the French-Italian border, with views over Piedmont and traces of old fortifications, but it adds up to roughly 3 hours round trip in total.

What animals live in the area? Chamois and ibex are common in Mercantour National Park and are frequently seen near Madone de Fenestre.