Erhai Lake (洱海) (etymologically Ear-shaped Sea because of its effective shape) is an alpine fault lake in Yunnan province, China. Erhai Lake was also known as Yeyuze or Kunming Lake in ancient times. The lake used to be a royal deer ranch for the Nanzhao Kingdom.
Erhai Lake is situated at 1,972 m above sea level. In size, the North-South length of the lake is 40 km and the East-West width is roughly 7-8 km. Its area is 250 km², making it the second largest highland lake of China, after Dianchi Lake. Its circumference reaches 116 km, its average depth is of 11 m and the total storage capacity of 2.5 billion m³.
The lake is sandwiched between the Cangshan Mountains to the West and Dali City. It starts at Dengchuan at its northern extremity and finishes at Xiaguan city in the South, receiving water from the Miju and Mici Rivers (in the North), the Bolou River (in the East) and smallers streams from the Cangshan Mountains. Yangbi River is the lake's outlet in the South and eventually flows into the Lancang River (Mekong River).
The lakeshore can be explored by hiking. Highlights include Erhai Lake Park and the Butterfly Springs on the Western bank. Islands on the lake are also available to visits (including Jinsuo Island (Golden Shuttle Island), Xiaoputuo Island, Guanyin Ge and Nanzhao Fengqing Island).
The lake is an important food source for the local people (Bais), who are famous for their fishing method: their trained cormorants catch fish and return them to fishmongers. The birds are prevented from swallowing their fish by rings fixed around their neck.
