Lac du Trou de l'Aigle

Lac du Trou de l'Aigle is a small high-mountain lake in the commune of Allos, in the Alpes-de-Haute-Provence department, right at the heart of the Mercantour massif. Sitting somewhere between 2,600 and 2,700 metres above sea level, at the foot of the peak that shares its name (2,961 m), it counts among the quieter, less-visited hiking destinations in this part of the French Southern Alps.

Where exactly is the lake?

Lac du Trou de l'Aigle lies within Mercantour National Park, a few hours' walk from the much better-known Lac d'Allos - one of the largest natural lakes in Europe at this altitude. The two lakes are sometimes combined into a single itinerary, but Trou de l'Aigle sits higher and further into the massif, surrounded by rocky ridges and scree, away from the busier paths leading to Lac d'Allos.

How do you get there?

Several approaches lead to the lake. One common starting point is the Col de la Cayolle, a pass at 2,326 m, from which the trail climbs toward the higher reaches of the massif. Other options run via the Pas de la Grande Barre or the Pas du Lausson. The final stretch of every route crosses broad scree fields and calls for sure footing - some sections are graded for scrambling or light alpinism (PD) rather than plain hiking. A more ambitious version of the outing links the lake with an ascent of Mont Pelat (3,051 m), the highest summit in this part of the Mercantour, before descending toward the refuge above Lac d'Allos.

What is there to see along the way?

The surrounding terrain is classic high-alpine scenery - bare ridgelines, wide scree slopes, and open views across the neighbouring peaks. Marmots and chamois, the two animals most associated with the Mercantour, are commonly spotted in the higher sections. Some multi-day variants of the route also swing past Le Cimet, an area known for its numerous waterfalls fed by meltwater from higher up the massif.

When is the best time to go?

Because of the altitude, the hiking season here is shorter than in the valleys below - snow can linger on the passes and scree slopes well into late spring. Summer and early autumn are the most reliable windows, when the trails are clear of snow and the rocky sections are at their safest.

FAQ

Where is Lac du Trou de l'Aigle located? In the commune of Allos, Alpes-de-Haute-Provence department, within Mercantour National Park, close to Lac d'Allos.

How high up is the lake? Roughly between 2,600 and 2,700 metres above sea level, at the foot of the Trou de l'Aigle summit (2,961 m).

Is the hike to the lake difficult? Yes - the final stretches cross scree fields and require sure footing, and some route variants involve light scrambling or alpinism-grade terrain.

Can the lake be combined with another hike? Yes, popular options link it with an ascent of Mont Pelat or with the route to Lac d'Allos and its refuge.