Tianchi — Heavenly Lake — occupies a glacial basin at 1,907 metres on the northern slope of the Bogda Shan, with Bogda Peak at 5,445 metres rising immediately to the south. The lake is not large — under five kilometres long — but its setting is extraordinary: spruce forests crowd the slopes above the shoreline, the snow-capped peak is visible on clear days reflected in the water, and the combination of elevation, forest, and mountain gives the place an alpine quality rare in the arid landscapes of this part of China.
The practical reality of visiting is that Tianchi is one of the most popular day trips from Ürümqi, and the infrastructure has developed accordingly: a ticket gate, a cable car, a tourist bus that loops the eastern shore, considerable crowds at weekends. The lake is best appreciated on weekday mornings in late May or early September, before the main summer rush. Those who walk the shore trail beyond the main viewpoints find themselves quickly in less-visited terrain; the path continues around the western shore and into the forest, where the crowds thin rapidly.
The lake's water is clear and very cold — swimming is possible but sharp. The eastern shore, where most facilities concentrate, has Kazakh yurts offering accommodation, horse rental, and food. The yurt experience here is more touristic than the genuine pastoral versions found at Sayram Lake or Karakul, but the horses and the terrain are real.