Don Juan Pond or Lake Don Juan is the saltiest known body of water on earth, with a salinity level of over 40%, that’s 18 times the ocean’s salinity! Discovered in 1961, the small lake is located in Victoria Land, Antarctica, and has a maximum length of 300 (985 ft) meters and width of 100 meters (328 ft). Lake Don is very shallow with a depth ranging between 10 to 30 centimeters! (4-12 inch). Because of the high salinity level the lake is almost never frozen, despite being in Antarctica!
Don Juan Pond is a small and very shallow hypersaline lake in the western end of Wright Valley, Victoria Land, Antarctica, 9 kilometres west from Lake Vanda. It is wedged between the Asgard Range to the south and the Dais Range to the north. On the west end is a small tributary and a rock glacier
It was named for two helicopter pilots, Lt. Don Roe and Lt. John Hickey, who piloted the helicopter involved with the first field party investigating the pond.
Due to its high salt levels, this small, shallow lake does not freeze even at very low temperatures.
Don Juan Pond is a small and very shallow hypersaline lake in the western end of Wright Valley (South Fork), Victoria Land, Antarctica, 9 kilometres (5.6 mi) west from Lake Vanda. It is wedged between the Asgard Range to the south and the Dais Range to the north. On the west end is a small tributary and a rock glacier. With a salinity level of over 47%, Don Juan Pond is the saltiest of the Antarctic lakes This salinity allows the pond to remain liquid even at temperatures as low as −50 °C (−58 °F) due to the interference of salts with the bonding of water molecules.
Don Juan Pond was discovered in 1961 by George H. Meyer. It was named for two helicopter pilots, Lt. Don Roe and Lt. John Hickey, who piloted the helicopter involved with the first field party investigating the pond
Don Juan Pond is a shallow, flat-bottom, hyper-saline pond. It has the highest total dissolved solids on record, with greater salinity than the Dead Sea or Lake Assal (Djibouti) (the same is true for Lake Vanda and perhaps other lakes in the McMurdo Dry Valleys). Salinity varies over time from 200 to 474 g/L, dominated by calcium chloride, and is over 18 times the ocean’s salinity and 1.3 times that of the Dead Sea. It is the only Antarctic hypersaline lake that almost never freezes. It has been described as a groundwater discharge zone. The area around Don Juan Pond is covered with sodium chloride and calcium chloride salts that have precipitated as the water evaporated.
The area and volume of Don Juan Pond vary over time. According to the USGS topographical map published in 1977, the area was approximately 0.25 km2 (62 acres). However, in recent years the pond has shrunk considerably. The maximum depth in 1993–1994 was described as “a foot deep” (30 cm). In January 1997, it was approximately 10 centimetres (3.9 in) deep;  in December 1998 the pond was almost dry everywhere except for an area of a few tens of square metres. Most of the remaining water was in depressions around large boulders in the pond
Studies of lifeforms in the hypersaline (and/or brine) water of Don Juan Pond have been equivocal