Traversée du lac d'Annecy

On the morning of August 15th, the shores of Lake Annecy transform into a bustling hub of anticipation as the Dauphins d'Annecy club orchestrates its 94th annual crossing. This event has deep roots, dating back to 1931, and today it draws nearly 2,000 swimmers from across the globe, all converging on the same alpine basin. As you stand on the starting pontoons, the scale of the landscape becomes clear: the lake is an glacial basin, a deep, dramatic basin carved by massive ice sheets that retreated over 15,000 years ago. This geological history provides the foundation for the water you are about to navigate, a body of water that breathes through the powerful Boubioz underwater spring, which feeds the lake from depths plunging as low as 81 meters.

The water and the view

While you swim, you are traversing a success story of environmental restoration. Stringent protection measures implemented since the 1950s have dramatically altered the underwater perspective; visibility has soared from a mere three meters in 1957 to an impressive 14 meters today, allowing you to catch glimpses of the lake floor as you glide through the water. As you look toward the horizon, the jagged silhouette of the Dents de Lanfon dominates the skyline. These limestone peaks rise to 1,824 meters, acting as a constant reference point for your navigation across the eastern bank. The water itself remains a constant companion, with seasonal temperatures that fluctuate from a sharp 6°C in winter to a more manageable 22°C in July and August, supported by a renewal cycle that refreshes the entire volume roughly every 3.8 years.

Race day logistics

The event offers four distances—1km, 2.4km, 5km, and 10km—each beginning from distinct points to accommodate different endurance levels. Logistics are a significant part of the entry fee, which ranges from 25 to 50 EUR; these funds support the massive safety operation involving over 200 volunteers, kayak escorts, and complex traffic coordination on the lake. If you are entering the 10km, be prepared to submit documented 5km reference times by June 30th to qualify. Whether you are swimming toward the finish at the Jardins de l’Europe or passing the historic, 'decrowned' towers of the Château de Châteauvieux, the course remains a blend of demanding physical effort and the serene clarity of one of Europe's most protected alpine environments.