Lac d'Annecy (Lake Annecy)

Lac d'Annecy, in the Haute-Savoie department of Auvergne-Rhône-Alpes, is widely regarded as one of the cleanest lakes in Europe, a status maintained by strict environmental regulations introduced in the 1960s that prohibit motorised boats and industrial discharge. The lake covers approximately 27 square kilometres and sits at 447 metres altitude, encircled by steep limestone ridges that rise to over 2,000 metres on the southern Bauges shore. The northern shore, closest to Annecy town, is the most visited: the Imperial Beach and the Pâquier lawns provide free public swimming and sunbathing, while a lakeside cycle and walking path runs for approximately 40 km around the entire perimeter. Pedal boats and stand-up paddleboards are available for hire from the Pâquier waterfront. Boat cruises depart from the Pâquier quays to the Abbaye de Talloires on the quieter eastern shore — a medieval Benedictine abbey now operating as a hotel. The lake's water is at its clearest in early summer before algae growth; by August the surface temperature reaches 22–24°C and the northern beaches fill completely by mid-morning on sunny days. A full loop of the lake by bicycle takes four to five hours at an easy pace. The canal mouth of the Thiou river where it drains the lake into Annecy old town, and the Pâquier gardens at dawn, are among the most photographed Alpine landscapes in France.