Lake Geneva is divided into three parts because of its different forms of formation (sedimentation, tectonic folding, glacial erosion): 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 Rhône outflow in Geneva. The Chablais Alps border is its southern shore, the western Bernese Alps lie over its eastern side. The high summits of Grand Combin and Mont Blanc are visible from some places. Compagnie Générale de Navigation sur le lac Léman (CGN) operates
Lake Geneva are for the most part rugged and sombre, while those of the northern shore fall in gentle vine-covered slopes, thickly set with villages and castles. The snowy peaks of the Mont Blanc are shut out from the western end of the lake by the Voirons mountain, and from its eastern end by the bolder summits of the Grammont, Cornettes de Bise and Dent d'Oche, but are seen from Geneva, and between Nyon and Morges. From Vevey to Bex, where the lake originally extended, the shores are enclosed by comparatively high and bold mountains, and the vista terminates in the grand