Yunnan's landscape comes from the collision of tectonic plates, and one consequence is a large number of hot springs. They range from municipal spa resorts an hour from Kunming to volcanic fields where the water boils out of the ground in a way that is genuinely alarming.
Anning
Anning, about forty kilometres west of Kunming, has been a spa town for centuries and is the most convenient option for a short stay. The springs are hot and rich in minerals, and there are both comfortable resort bathhouses and simpler public pools where local families come for an afternoon. The town sits in a wooded valley, and a bath followed by a meal of local Yunnan food is an easy day away from the city.
Tengchong Rehai
Tengchong, in the far west near the Myanmar border, is a volcanic area with a geothermal field known as Rehai, the hot sea. Here the attraction is not the bathing but the geology: steaming vents, mud pools bubbling, water boiling out of the rock at close to a hundred degrees, and a river running hot through the valley for hundreds of metres. Boardwalks keep visitors safe, and there are bathing pools lower down where the hot water is mixed to a comfortable temperature. Tengchong also has its own volcano park with recent craters, and an old jade-trading town with wooden architecture.
Other options
There are springs and spa resorts around Yangzonghai and Fuxian Lake east of Kunming, and in the mountains west of Dali. In Xishuangbanna, a few resorts have thermal baths in tropical surroundings. Standards vary widely: the best places have graded pools at different temperatures, and the cheapest are simply a hot pool behind a wall.
Practical notes
Most Chinese hot springs require swimwear, and many rent it. Bring your own towel if you are particular. Do not stay in very hot water for long periods, drink water, and avoid alcohol before bathing; if you have heart problems or high blood pressure, keep to the cooler pools and keep sessions short. Tengchong is best reached by flight from Kunming, about an hour, and the Rehai site charges a substantial admission fee.
