Namtso Lake, also called Lake Nam, is a mountain lake on the border between Damxung County of Lhasa Prefecture and Baingoin County of Nagqu Prefecture in the Tibet Autonomous Region of China, approximately 112 kilometres (70 mi) from Lhasa.

In Tibetan, Namsto means "Heavenly Lake", and its breath-taking beauty really deserves the fame as the water here is a storybook crystal-clear blue. Any tour to Tibet without visiting Namtso Lake is incomplete. Namtso Lake was formed by Himalayan tectonic plate movements in Paleogene age. Occupying a surface area of 1,920 square kilometers, this salt lake is the largest lake in the Tibet Autonomous Region with an altitude of 4,718 meters. Lying at the foot of Nyainqentanglha Mountain, Namtso Lake is full of islands and islets in varied forms with birds sporting over the water surface.

Besides its gorgeous and enchanting scenery, Namtso is a perfect to experience Tibetan Buddhism culture. It is respected as one of the four holiest lakes and the seat of Paramasukha Chakrasamvara by Buddhist pilgrims. Five islets scattering in the vast sapphire blue lake is said to be the incarnation of the Buddha of Five Directions, which are worshiped by every pilgrim circumambulating the lake. At the lakeside there are two standing stone pillars, each rising 30 meters and eight meters apart. Some Tibetans believe it is the Gate God of the Nam Co Lake. Buddhist pilgrims believe that, by circling the lake once and circling the Duoqiong Island for 12 times in Tibetan year of the sheep, they could acquire infinite virtues and profound wisdom. Soul of every visitor visiting here could undoubtedly be cleansed by the pure lake water, as well as pilgrims' loyalty towards Buddha.