Laguna Miscanti is a brackish water lake located in the altiplano of the Antofagasta Region in northern Chile.

This 13.5 square kilometres (5.2 sq mi) large heart-shaped lake has a deep blue colour and developed in a basin formed by a fault.

[18] In the past, the two lakes were connected, producing a large waterbody which has left beach terraces in the landscape[12] and whose water levels were about 20 metres (66 ft) higher than today.

[20][21] A number of creeks enter into Laguna Miscanti from the north, east and south (Quebrada de Chaquisoqui[1]), and there are two springs on its northern shores.

[27] The catchment of the lake consists mainly of volcanic and sedimentary rocks ranging from Miocene to Holocene age and covers a surface area of 320 square kilometres (120 sq mi),[12] with Quaternary volcanoes that reach elevations of 5,000–6,000 metres (16,000–20,000 ft).

[18] In the late Pleistocene and early Holocene the climate was much wetter and lakes expanded,[18] especially during the first stage[30] of the Central Andean Pluvial Event.

[31] The late Pleistocene—early Holocene wet period was particularly noticeable in the Altiplano, where two separate phases of the Lake Tauca occurred.

[32] The last glacial maximum was drier[33] and colder, leading to a total disappearance of vegetation[34] and a drying of the lake between 22,000 and 14,000 years ago.

[43] Fauna that inhabits the area includes birds like flamingos,[44] Fulica ardesiaca (Andean coot), Fulica cornuta (Horned coot), Larus serranus (Andean gull), Lophonetta speculiarioides (Crested duck) and Podiceps occipitalis (silvery grebe),[45] and mammals like Ctenomys opimus (Highland tuco-tuco), Lagidium viscacia (Southern viscacha), Phyllotis darwini (Darwin's leaf-eared mouse), Pseudalopex culpaeus (culpeo) and Vicugna vicugna (vicuña);[44] the two lakes are important breeding sites for the horned coot.