Under the designation Lake Constance (German: Bodensee) one summarizes the three independent bodies of water Obersee ("Lake Superior"), Untersee ("Lake Inferior") and Seerhein ("Lake Rhine"), lying in the northern Alpine foreland. Thus, it concerns two independent lakes (standing waters) and one connecting river (current water).Lake Constance is situated in Germany, Switzerland and Austria near the base of the alps. Specifically, its shorelines lie in the German federal-states of Bavaria and Baden-Württemberg, the Austrian federal-state of Vorarlberg and the Swiss cantons of Thurgau and St. Gallen. The Rhine flows into it from the south.
The freshwater lake sits at 395 m above sea level and is Central Europe's third largest, after Lake Balaton and Lake Geneva. It is 63 km long, and at its widest point, nearly 14 km. It covers approximately 571 km² (208 mi²) of total area. The greatest depth is 252 m in the middle of the eastern part (Obersee). Its volume is approximately 55 km³. The lake has four parts: Obersee (main, 476 km²), Überlinger See (north, 61 km²), Untersee (west, 63 km²), and the Zeller See and Gnadensee (northwest). The regulated Rhine flows into the lake in the southeast, through the Obersee, the city of Konstanz and the Untersee and flows out near Stein am Rhein. Lake Constance provides fresh water to many cities in south Germany.