Owl Creek Hot Springs, in Lemhi County, Idaho, delivers thermal water at around 38°C (100°F). The site combines an indoor bath, a rotenburo-style outdoor bath, a sauna and massage.
Insider tip — Located roughly 15 km south of Horse Creek Hot Springs in the same Salmon River wilderness of central Idaho. A primitive soaking pool fed by natural geothermal waters. Best visited in autumn when the summer crowds thin and the aspen turn gold.