Spas with adults only

A beachfront resort spa in North Beach, Miami with cryotherapy, a floating salt bath, sauna, steam and a cold plunge, open to walk-ins and day-pass guests.

A Fallston, Maryland day spa specializing in Japanese head spa treatments, serum infusion facials, dermaplaning and body contouring, with walk-ins accepted.

Day spa in South Scottsdale focused on facials and a signature holistic massage, with sauna, steam room, thermal pool and cold plunge on site.

A Korean jjimjilbang in Houston with clothing-optional bathing pools, sauna and steam rooms, $58 day pass, adults 18+ only, walk-ins welcome.

A Finnish kelo-log banya in Newton with sauna, steam room and cold plunge, alternating men's and women's days, day passes from $69.

A Korean jjimjilbang-style spa in Palisades Park, NJ, with ten heated sauna rooms, hot tubs, cold plunge and a $69 day pass, open daily 9am to 2am.

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.

Adults-only spa inside the all-inclusive Ocean Riviera Paradise resort in Playa del Carmen, with sauna, Turkish bath and four treatment options via day pass.

A co-ed recovery studio in Saugus with cold plunge tubs, dry sauna, red light therapy and a mobility floor, day pass $50.

A Birmingham, Michigan day spa built around waterless volcanic rock treatments, with V-steam, facials, massage and a steam room for adults and couples.

Soft Handz is an adults-only day spa near Minneapolis/St. Paul with sauna, steam room, jacuzzi and cold plunge, open to walk-ins for a $50 day pass.

Korean-style bathhouse in Katy with gender-separated nude bath areas, themed saunas and a $55 day pass covering full-day access.

Adults-only resort spa in Sedona with outdoor hot tubs, steam rooms and a 30-treatment menu, open daily with walk-ins and day passes.

A moderately priced day spa in Chicago's Lakeview neighborhood focused on Chinese-style head and scalp treatments, open to adults 16 and up.

Oakland float and sauna studio near Grand Lake with private float tanks, infrared sauna cocoons and cryotherapy, open daily 11am-8:30pm.

A Mount Pleasant recovery studio near Charleston offering cryotherapy, compression therapy and infrared sauna sessions, open daily except Sunday.

Day spa in Steiner Ranch, Austin, offering sauna, steam room, thermal pools, cold plunge and a signature scalp treatment for adults, open Monday through

A halotherapy day spa in West Elkridge, near Baltimore, built around a salt cave, massage rooms and a yoga studio, aimed at solo adult visitors.

A no-frills contrast therapy studio in Carmel, Indiana, built around a 30-minute sauna-and-cold-plunge circuit for solo visitors.

East Town Spa in Milwaukee's Juneau Town combines a full-service salon and med spa with a thermal circuit of sauna, steam, pools and cold plunge.

A moderate-priced day spa in Minnetonka with a sauna, steam room, thermal pool and cold plunge, set up for couples and adults-only visits.

A moderate-priced day spa in Des Peres, just west of St. Louis, open six days a week with a relaxation lounge and treatments geared toward couples and adults.

A medical spa on San Antonio's Far West Side offering massage, facials, injectables and laser hair removal, open weekdays and Saturday mornings.

Day spa in a Montebello strip mall plaza offering facials, massages and body treatments, open daily with walk-ins accepted.