Lacs de Prals

Lacs de Prals is a cluster of glacial mountain lakes above Saint-Martin-Vésubie, tucked into the high Mercantour National Park in the Alpes-Maritimes. Sitting at the head of the Upper Vésubie valley, the lakes occupy a rocky glacial basin ringed by bare ridgelines and alpine pasture, and rank among the best-known day hikes in this part of the French Maritime Alps.

How do you get there?

The usual starting point is the Madone de Fenestre sanctuary, reached by road from Saint-Martin-Vésubie and sitting at roughly 1,820 m altitude. From there a loop trail climbs past grazing pastures and rocky outcrops toward the Baisse des Cinq Lacs, a pass above 2,300 m that marks the high point of the circuit and opens up a view over the whole chain of lakes. The full loop covers around 8 km, with about 530 m of elevation gain, and typically takes hikers four to five hours to complete. It's considered a demanding outing, so a reasonable fitness level and proper trekking footwear are worth planning for.

What will you find at the lakes?

The name "Lacs de Prals" covers a small group of lakes — several accounts count five — scattered across a rocky, glacially carved basin. The water takes on a striking, saturated colour against the surrounding scree slopes and bare granite ridges, and the sparse alpine vegetation that clings to the rock adds bursts of green among the grey. It's a landscape typical of Mercantour's high country: stark, stony, and shaped almost entirely by ice and erosion rather than forest cover.

Mercantour National Park is one of the last strongholds of large alpine wildlife in France, and the Prals basin is no exception. Hikers regularly spot chamois grazing on the steep slopes, and the whistling calls of marmots often carry across the valley long before the animals themselves come into view — one of the reasons this route draws so many nature-focused walkers.

Who is this hike suited for?

Given the altitude, the elevation gain, and the rocky ground near the pass, the Lacs de Prals circuit is best suited to hikers with some mountain experience rather than a casual family stroll. It's more of a full-day outing for people ready to spend several hours on open, high-altitude terrain where weather can shift quickly. In return, it delivers some of the most distinctive glacial scenery in the whole Mercantour range.

Frequently Asked Questions

Where does the hike to Lacs de Prals start? Most hikers begin at the Madone de Fenestre sanctuary (around 1,820 m), reached by road from Saint-Martin-Vésubie.

How long does the hike take and how difficult is it? The loop is roughly 8 km with about 530 m of elevation gain, usually taking four to five hours. The rocky, high-altitude terrain makes it a demanding rather than easy route.

How many lakes make up Lacs de Prals? The name refers to a small cluster of glacial lakes within a single rocky basin, with several sources counting five separate bodies of water.

What wildlife might you see along the way? Chamois and marmots are commonly observed around the lakes, both typical of the high-altitude fauna found throughout Mercantour National Park.

Is this route suitable for beginners? Because of the altitude, the elevation gain, and the rocky sections near the Baisse des Cinq Lacs pass, prior hiking experience and solid fitness are recommended.