Traversée du Lac des Vieilles Forges

The water is surprisingly still, yet you feel a subtle, rhythmic pulse beneath your stroke. This is the Lac des Vieilles Forges, where the artificial cycles of the nearby Revin hydroelectric plant—the third largest pumped-storage facility in France—create a hidden, internal movement. As you track the 2.5 km loop, the depth beneath you fluctuates, reflecting the 800 MW capacity of the facility that shifts massive volumes of water between this basin and the upper reservoir at Marquisades. You are swimming in an industrial engine disguised as a natural sanctuary.

Beneath the surface, the landscape is far from uniform. Beside the standard lake-dwellers like carp and pike, you might spot the occasional bladderwort, a carnivorous plant that thrives here, alongside the delicate fronds of the royal fern clinging to the margins. Keep your focus on your rhythm, as the biodiversity here is dense; the area supports thirteen species of dragonflies, while the shoreline is a known habitat for the alpine newt and the venomous adder, which occasionally makes its presence known in the tall grasses near the water's edge. The name of the lake itself is a relic of the 16th century, honoring Witacker, a master of forges who once operated the ironworks that defined this valley long before it became a reservoir.

Historical gravity of Les Mazures

As you navigate the circuit, it is impossible to ignore the weight of the surrounding forest. The commune of Les Mazures carries a somber legacy; during the second year of World War II, this site hosted a forced labour camp where 288 Jewish men from Antwerp were interned before their final deportation to Auschwitz. The modern tranquility of the Traversée du Lac des Vieilles Forges, now in its 12th year, stands in stark contrast to the historical isolation of this landscape. The event brings a different energy to the water every July, with distances ranging from a 500m sprint to a demanding 10km marathon, all managed by the ASN Charleville-Mézières. Whether you are aiming for the prize money in the long-distance category or testing your endurance in the 2.5km loop, the strict time limits—3h30 for the 10km—are enforced to ensure safety, reflecting the technical nature of a course that demands consistent, measured pacing.