Formerly a single unitary lake, it is now an expansive salt flat divided into four greater sections (Dabusun, Big/Small Bieletan, Suli, and N./S.

The area is heavily exploited for its valuable salt, mineral, and rare earth reserves but parts are also protected as a national park and contribute to regional tourism.

[1] Cha'erhan is the pinyin romanization of the Mandarin pronunciation of 察爾汗, a modification of the original transcription into Chinese characters of the same name;[1] it is also sometimes clipped into Charhan in English sources.

[6][7][a] Qarhan is part of the larger Qaidam Basin, lying between the Kunlun Mountains to the south, the Altun to the west, and the Qilian to the north.

Qarhan's lakes lie between 2,675–2,680 m (8,780–8,790 ft) above sea level, with Dabusun and North Hulsan being the lowest and Xiezuo being the highest.

[5] The effect of elevation is such that despite lying on the same latitude as Greece, Algeria, and Virginia in the United States, Qarhan has a mean annual temperature of 0.1 °C (32.2 °F).

[10] There is also contribution of about 1% from mineral springs,[5] especially on the north end of the playa,[16] which play an important role in the chemical composition of the sediment.

The major expedition to the Qarhan Playa was undertaken in 1955–6,[28] but the area's important carnallite (and thus potassium) reserves were discovered accidentally by geologists Zheng Mianping and Liu Dagang during a stroll on 2 October 1957.

[18] During a 2016 inspection tour, Chinese Communist Party general secretary Xi Jinping praised the importance of the factories and their workers to the entire country but emphasized the need for Qarhan's development to be environmentally responsible.

[19] The fertilizer factory is now open to the public for free tours, and its parent company maintains a nearby museum covering the geology of the playa and hosting various salt sculptures.