Chinese Er Hai or Erh Hai
Lake, western Yunnan province, China.
It lies in a deep basin at the foot of Mount Diancang between the upper Yangtze (Chang; there called the Jinsha) and Mekong rivers; it is about 30 mi (50 km) long and 610 mi (1016 km) wide. The south of the basin has connections to eastern Yunnan and to Sichuan province and is on the main route southwest to Myanmar (Burma). The surrounding area was brought under Chinese control during the Yuan dynasty (late 13th century).