Lac de Longemer

Lac de Longemer lies in the upper Vosges valley approximately 5 kilometres east of Gérardmer in the Grand Est region of France, at an altitude of around 730 metres. It is the second of the three linked Vosges lakes — Gérardmer, Longemer and Retournemer — and is notable for its elongated shape, stretching roughly 1.8 kilometres along a forested corridor. The shoreline combines narrow grassy banks and low rocky outcrops, with the water taking on a dark blue-green hue characteristic of high-altitude glacial lakes. The lakebed is sandy-gravel, and visibility in the shallows is generally good. A supervised swimming area is marked at the eastern end near the Camping du Lac, operational from July through August. Lifeguard cover is provided during this period and conditions are calm, with minimal wind exposure thanks to the surrounding Vosges forest ridgelines. The lake is not tidal and waves are absent; swimming conditions are gentle and well-suited to children and casual swimmers. Water temperature in July typically reaches 20–22°C, somewhat cooler than Lac de Gérardmer due to the higher altitude. The adjacent Camping du Lac de Longemer provides the primary amenities for day visitors: kayak and stand-up paddleboard hire, a snack kiosk, and picnic meadows running directly to the waterline. There are no dedicated sun-lounger rentals and the shore is grassy rather than sandy, so visitors typically bring their own towels and mats. Public toilets are located at the camping reception. Parking is available in a small unpaved lot near the camping entrance off the D417. Dense Vosges fir forest frames both long sides of the lake, and marked walking trails departing from the eastern end connect to the Lac de Retournemer, less than 1 kilometre on foot, and to the GR5 long-distance trail. Cyclists on the Route des Crêtes frequently stop here. Public transport to Longemer is limited and a car is effectively required for most visitors.