Funtensee

The lake lies at an elevation of 1601 m and has a surface area is 3.5 ha. Its outflow toward the Schrainbach is subterranean at a location called Teufelsmühle. On its shore is the Kärlinger Haus mountain hut which is open for the summer season; in addition, there is a winter room available. The valley is surrounded by the mountains Viehkogel (2,158 m), Glunkerer (1,932 m) and Stuhljoch (2,448 m)^[3] which lead to the Funtenseetauern mountain (2,578 m), named after the lake.

Earliest evidence of use of the area for grazing can be traced to ca 1604–1619.^[3] Around 1870 there was evidence of eight active Kaser (living quarters/stables) causing concerns of overgrazing.^[1] The Funtenseealm (hut) was active until 1964.^[3]

Known as the coldest spot in Germany, the lake is the site where the country's record lowest temperature, −45.9 °C (−50.6 °F),^[4][5][6] was recorded on 24 December 2001. It is theorized that due to the unique situation of trapped cold air, a temperature of −55 °C (−67 °F) is possible.^[7] The extreme cold spot at the lake is said to result in a reverse tree line, as no trees can grow at any point below about 60 m above the lake,^[6] although studies have found that it may be the result of overgrazing animals.^[3] Temperatures are regularly monitored by a private weather station installed by Jörg Kachelmann.^[8]