Tibet sits on the collision zone between two continents, and the heat under the plateau shows up as geysers, boiling springs, mud pools and steam vents. The most accessible example for a visitor based in Lhasa is Yangbajain, in Damxung county about ninety kilometres north of the city on the road towards Namtso, where a wide, flat valley is dotted with steaming pools and the ground itself is warm.
The geothermal field
Yangbajain is one of the largest geothermal fields in China and has been exploited for power since the 1970s, when a generating station was built to supply the Lhasa grid. The wells, pipes and cooling towers are visible from the road, and the sight of industrial steam drifting across an empty high-altitude valley is a strange one. Alongside the power plant there are natural springs, boiling pools and fumaroles, and the ground temperature in places is high enough to be dangerous, so the area is fenced and visitors are kept to the marked parts and to the developed bathing areas.
The bathing
There are developed hot spring pools here, some attached to hotels and some simple outdoor baths, and a smaller cluster of springs further along the valley. The water comes out of the ground very hot and is cooled into the pools; the air outside is cold for much of the year and can be below freezing even in spring, which makes the contrast the point. Facilities are basic: changing rooms, a place to leave clothes and a pool. Because the site is above four thousand metres, a long soak is a bad idea on a first day at altitude, and it is more sensible to come after you have acclimatised.
Practical notes
Yangbajain is about two hours from Lhasa by road and is normally visited on the way to or from Namtso, or as a half-day trip on its own. There is nowhere to stay except the small hot spring hotels, and food is limited to the simple restaurants on the main road. Bring a towel, a change of clothes and something warm to put on afterwards, since the wind is sharp. The drive itself passes through high pasture with nomad camps and grazing yaks, and the mountain views along the way are as good as anything at the destination.
