Spas with sauna

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.

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.

Hotel spa inside Dua Miami, Autograph Collection in Brickell, open daily 9am-6pm, with sauna, steam room, cold plunge and couples massage rooms.

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 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 and pool complex inside Loews Miami Beach Hotel, open to hotel guests only, with sauna, steam, cold plunge and thermal circuits.

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.

Andalusian-style resort spa at the base of Camelback Mountain with saunas, steam rooms, a hammam and three pools, open to guests 21 and up.

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

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.

Hotel spa at The Phoenician in Scottsdale, open to guests 18+ who book a massage, facial, or body treatment, with sauna, steam room and a rooftop pool.

Adults-only hotel spa in downtown Napa with thermal circuits, sauna, steam and cold plunge, plus massages, facials and medical aesthetics.

A reservation-only day spa in Sandy, Utah, built around scalp spa treatments, plus sauna, steam, cold plunge and thermal pools.

Adults-only hotel spa at the Hilton Orlando with a sauna, steam room, cold plunge and thermal pools, plus couples treatments and HydraFacials.

Adults-only hotel spa at W Scottsdale with thermal circuits, sauna, steam, cold plunge and a robotic Aescape massage option.

A St. Paul wellness studio in Macalester-Groveland offering infrared sauna, float tanks, salt therapy and cold plunge by reservation, adults-only, day-pass

Kamalaya Koh Samui is an adults-only destination spa and wellness retreat on Laem-Set Rd with over 100 treatments, thermal circuits and multi-day health

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 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.

An adults-only wellness retreat on Ubud's Ayung River offering multi-day healing programmes, thermal circuits and plant-based cuisine by reservation only.