Spas with thermal pool

Palm Springs, California

Adults-only hot springs resort on Miracle Hill in Desert Hot Springs with private mineral tubs, a Finnish sauna, salt room and 35 spa treatments.

Duluth, Georgia

A 24-hour Korean bathhouse in Duluth with a $30 day pass, sauna rooms, cold plunge, thermal circuits and a junior Olympic pool.

Tucson, Arizona

Adults-only hotel spa at El Conquistador Tucson with a salt therapy lounge, heated outdoor pool and mountain views, day passes available to hotel guests.

Miami, Florida

Hotel spa deck in downtown Miami with sauna, steam room, cold plunge and thermal pools overlooking Biscayne Bay, day passes from $50.