Spas with adults only

Seattle, Washington

A Russian-style bathhouse in South Lake Union with a hydrotherapy circuit and sauna, open to walk-ins daily except Monday, adults only.

Chicago, Illinois

A 24-hour Korean bathhouse and sauna complex in Niles near Chicago, with 11 heat rooms, hot and cold pools, and a $45 day pass covering walk-in access.

Denver, Colorado

Adults-only bathhouse on West Colfax Ave in Denver with a steam room, sauna, hot tub and relaxation lounge, open daily except Tuesday.