Situation With a surface area of 5.45 km2 (2.10 sq mi) it is one of the largest natural lakes of France. It is the fourth-largest natural lake in the
Auvergne-Rhône-Alpes region, after
Lake Geneva (although partly in
Switzerland),
Lake Annecy and the
Lac du Bourget. It has a maximum depth of 71 metres (233 ft). It is part of the Avant-Pays savoyard, formerly known as the Petit-Bugey. It is noted for its blue-green colour and seven hot water springs. The communities of
Aiguebelette-le-Lac,
Lépin-le-Lac,
Saint-Alban-de-Montbel,
Novalaise and
Nances border the lake, while the
Chaîne de l'Épine ridge lies to the east with its high point at Mont Grêle (1,425 metres or 4,675 ft), south-southeast of the lake. At the southern end there are two islands, La Petite Île and La Grande Île, the latter of which has a chapel, the Chapelle Saint-Vincent, administratively part of the commune of Lépin-le-Lac.
Transport The lake is served by the railway line from
Saint-André-le-Gaz to
Chambéry; the section between
Lépin-le-Lac-La Bauche station (southwest) and
Aiguebelette-le-Lac station (southeast) offers panoramic views on the lake. The
A43 autoroute is north of the lake. ==Climate==