Lac de Lessy: hike from Le Petit-Bornand (Glières-Val-de-Borne)

Lac de Lessy is the mountain lake of Glières-Val-de-Borne. It lies at 1,733 m, at the foot of the Pic de Jallouvre, the big summit that closes the valley above Le Petit-Bornand. No road leads there: you walk up in half a day from the car parks on the Route de Puze, which starts outside the town hall, a few hundred metres from the campsite.

Three routes up to the lake

Via Cenise is the most direct and best documented route. From the Cenise car park, the path climbs over the Col de Sosay, then drops down to the lake. The tourist office and Visorando agree: about 8.5 km return, close to 600 m of ascent, a little under 4 hours of walking, rated difficult. This is a real mountain hike, not a stroll.

Via Paradis, you start from the lower Paradis car park and reach the lake over the Col de la Forclaz. The ascent is similar, between 500 and 600 m. Sources disagree on the difficulty: the tourist office rates it "very difficult", while other guides describe it as fine for children who are good walkers. We would rather not decide before walking it again ourselves: with a family, go for the Cenise route, whose level the sources agree on.

Via Mayse, from the hamlet of La Ville, is the long version, along the forest road, past the Mayse chalets and over the Col de la Forclaz. Keep it for walkers who want a big day out.

At the lake

The lake was reopened to fishing in 2009 after sealing works; it has its own fishing rules, so check them before you cast. The tourist office reports marmots and ibex in the area. According to the bylaw posted on its route sheets, swimming, fires and camping are banned at the lake: it is a place for a picnic, not a swim.

Our advice

Set off early in summer, take water, warm layers and a map or the official GPX track. Turn back if a storm is forecast: the lake is more than 1,000 m above the village. Out of season, check the snow conditions before going up.