Tanggangzi Hot Spring Sanatorium is one of the four rehabilitation centers in China, located at the south of the city 15km, with an area of 650,000 square meters. Hot spring water is odorless, clear and transparent, with a water temperature of 72℃, and contains more than 30 trace elements such as potassium, magnesium, hydrogen and sodium. Hot spring water and hot mineral mud combined with massage, acupuncture, wax therapy and photoelectric therapy have obvious curative effects on rheumatoid arthritis, dermatosis and traumatic sequelae. The sanatorium has elegant environment and unique style. The "Dragon Palace Hot Spring" where the last Chinese emperor Boyi lived and the "Dragon Palace Villa" built by the northeast warlord Zhang are well preserved, and now they have become convalescent and tourist attractions.