Namtso

Namtso sits at about 4,718 metres on the Tibetan Plateau, and at that height the colour of the water is the first thing that stops people: a saturated, almost mineral blue that shifts to turquoise in the shallows and to slate under passing cloud. It is the largest lake in the Tibet Autonomous Region, roughly 1,900 square kilometres of salt water with no outflow, reaching a depth of around 125 metres. The Mongolian name, Tengri Nor, means "Heavenly Lake", and the description is literal - the far shore is often lost in haze, and the sky seems to sit directly on the water.

The lake's southern horizon is the Nyenchen Tanglha range, whose highest summit rises to 7,162 metres; its snowfields and glaciers fill the view from almost anywhere on the eastern shore, and on still mornings they repeat themselves in the water. The road from Lhasa crosses the range at the Laken La, a pass at about 5,190 metres strung with prayer flags, and the first sight of the lake from the top - a long blue band laid across brown steppe - is one of the great arrivals of high Asia. Nomadic herders still pitch their camps along the shore, and the lake is an important stop for migratory birds.

Namtso is a sacred lake in Tibetan Buddhism, and pilgrims walk around it as a devotional circuit. The spiritual focus of the eastern shore is Tashi Dor, a peninsula reaching into the lake from the south-east corner, where a small monastery and a cluster of hermit caves have drawn pilgrims and practitioners for centuries. The lake holds five sizeable uninhabited islands, the largest about 2.1 km long, and hermits once reached them by walking across the frozen surface at the end of winter to spend the summer in retreat - a practice that is no longer allowed. In winter the lake freezes, and the light, the ice and the emptiness make it a different place altogether.

What lingers after a visit is the scale: a lake you cannot see across, set at an altitude where the air is thin, the light hard and clear, and the silence broken only by wind and prayer flags. The climate is alpine - frigid, very dry winters and cool, rainy summers - so the lake shows a different face in every season.

Getting there

Damxung, the county town, is the gateway, about 65 km from the lake by straight line; Lhasa lies roughly 112 km to the south-south-east. The nearest airport is Lhasa Gonggar International Airport (LXA), about 160 km away. A paved road completed in 2005 leads from Damxung over the Laken La to Tashi Dor, and most visitors come on a day trip or an overnight stop from Lhasa.