Erhai is situated at 1,972 metres (6,470 ft) above sea level. In size, the North-South length of the lake is 40 kilometres (25 mi) and the East-West width is roughly 7–8 kilometres (4.3–5.0 mi). Its area is 250 square kilometres (97 sq mi), making it the second largest highland lake of China, after Dianchi Lake. Its circumference reaches 116 kilometres (72 mi), its average depth is of 11 metres (36 ft) and the total storage capacity of 2.5 billion cubic metres (2,000,000 acre⋅ft). The lake serves as a backdrop to all of Dali City and sandwiches Dali Old Town in the west against the Cang Mountain. The lake's head is at Shangguan Town, its northern extremity, and its southernmost point is at Xiaguan Town. The lake receives water from the Miju and Mici Rivers in the north, the Bolou River in the east, and smallers streams from the Cang Mountains in the west. Yangbi River, to the south, is the lake's outlet and eventually flows into the Lancang River (Mekong River).