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
River Awbeg rises about two miles north of Liscarroll and flows south and then north and west under Annagh Bridge to join the first branch at Scart Bridge. From there, the river flows south through Buttevant and east through Doneraile, turns south near Shanballymore and through Castletownroche to enter the Blackwater at Poulcormac near Bridgetown Abbey. North of Buttevant the river flows through flat agricultural land, while south of Buttevant the river generally flows through a narrow, steep-sided valley with wooded sides. For the most part the river flows over Carboniferous limestone. The river supports a range of plant species including dropwort,