Visitors enjoy the picturesque scenery of Basum-tso Lake in Nyingchi of southwest China's Tibet Autonomous Region, May 4, 2011. Basum-tso means "green water" in Tibetan. The entire area of the pristine lake features jokuls, forests and an islet where standing a monastery with a history of more than 1,500 years. [Xinhua/Chen Haining]