Lake Erhia is an extensive stretch of water covering some 320 sq km, 40 km long and 8 km wide, beginning from Eryuan in the north to Xiaguan in the south, sitting at an elevation of nearly 2 000 metres above sea level.

• 洱海北起洱源，南至下关，长40千米，平均宽8千米，面积320平方千米，海拔1980米。