Chiang Mai is one of Thailand's main destinations for natural hot springs, Sankampaeng probably the best known of them.
Chiang Mai is blessed with excellent scenery and its hot springs are set against trees, hills and countryside which make them excellent locations for treks and other activities. Water from the province's springs has very high sulphur content and this is believed to be the main reason its curative qualities. If you are in Chiang Mai, you really should try to visit a hot spring.
If you are in Chiang Mai for a longer period, try more of the province's hot springs.