Untersee (Lake Constance)

Untersee
View from an aeroplane above Rickenbach (CH) of the Untersee and the island of Reichenau (D) with Lake Überlingen (D), the northwestern part of the Obersee (D/CH/A) behind.
Untersee
Untersee
Untersee
Untersee
Untersee
LocationBaden-Württemberg (Germany)
– Cantons of Thurgau and Schaffhausen (Switzerland)
Coordinates47°41′42″N 9°1′28″E / 47.69500°N 9.02444°E / 47.69500; 9.02444
Primary inflowsSeerhein, Radolfzeller Aach and smaller streams
Primary outflowsHigh Rhine
Surface area62 square kilometres (24 sq mi)
Average depth13 metres (43 ft)
Max. depth45 metres (148 ft)
Water volume0.8 cubic kilometres (0.19 cu mi)
Shore length187 kilometres (54 mi)
Surface elevation395.11 metres (1,296.3 ft)
IslandsReichenau, the Werd islands
SettlementsRadolfzell am Bodensee
1 Shore length is not a well-defined measure.

The Untersee (German for Lower Lake), also known as Lower Lake Constance, is the smaller of the two lakes that together form Lake Constance. The boundary between Switzerland and Germany runs through it. The lake surrounds several islands, the largest being Reichenau Island.