Pagsum Co (Chinese: Bāsōng Cuò 八松错, Tibetan: brag gsum mtsho བྲག་གསུམ་མཚོ།), literally meaning “three shores” in Tibetan, is a lake covering 28 square kilometres in Gongbo'gyamda County, Nyingchi Prefecture of the Tibet Autonomous Region in China, approximately 300 km east of Lhasa in Tibet. At 3,700 metres over sea level it is about 18 km long and has an average width of approximately 1.5 kilometres. The deepest point of the green lake measures 120 metres.

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