Also known as Tangre Tso or Tanggula Yumco, Tangra Yumco is the largest holy lake worshipped by Xizang’s primitive Bon religion and the third largest lake in Xizang. Stretching from north to south, the lake resembles a shoe sole and is surrounded by mountains on three sides, with only a gap on the eastern side of Dago Mountain on its southern bank.

Dago Mountain features seven peaks in a row. Their dark rock faces are topped with snow, looking exactly like seven neatly arranged pyramids. Both the mountain and the lake are regarded as sacred sites by Bon believers.