Lake Geneva

Lake Geneva or Lake Léman (French: Lac Léman, Le Léman, sometimes Lac de Genève, German: Genfersee) is a lake in Switzerland and France. 

It is one of the largest lakes in Western Europe. 59.53% 345.31 km2 (133.32 sq mi) of it comes under the jurisdiction of Switzerland (cantons of Vaud, Geneva, and Valais), and 40.47% 234.71 km2 (90.62 sq mi) underFrance (Haute-Savoie).

The first recorded name of the lake is Lacus Lemannus from Roman times; Lemannus comes from Ancient greek Limanos, Limènos Limne Λιμένος Λίμνη meaning port's lake; it became Lacus Lausonius, although this name was also used for a town or district on the lake, Lacus Losanetes and then the Lac de Lausanne in the Middle Ages.Following the rise of Geneva it became Lac de Genève (translated into English as Lake Geneva). 

In the 18th century, Lac Léman was revived in French and is the customary name in that language (except in the canton of Geneva). In contemporary English, the name Lake Geneva is predominant. 

Lake Geneva is divided into three parts because of its different reasons of formation (sedimentation, tectonic folding, glacial erosion):

• Haut Lac (Upper Lake), the eastern part from the Rhone estuary to the line of Meillerie–Rivaz
• Grand Lac (Large Lake), the largest and deepest basin with the lake's largest width
• Petit Lac (Small Lake), the most south-west, narrower and less deep part from Yvoire–Promenthoux next Prangins to the exit in Geneva

According to the Swiss Federal Office of Topography, swisstopo, Lac de Genève designates that part of the Petit Lac, which lies within the cantonal borders of Geneva (excluding the cantonal exclave Céligny), so about from Versoix–Hermance to the Rhone outflow in Geneva.   [ source ]