Spas with thermal pool

Austin, Texas

Lakeside day spa near Austin offering a $150 day pass with pools, steam room, sauna and relaxation lounges, open daily 9am–9pm.

Tucson, Arizona

Hotel spa at Loews Ventana Canyon Resort, Tucson, with eight treatment rooms, an adults-only pool, and a 24-hour fitness center; open daily 9am–6pm.

Miami, Florida

Adults-only hotel spa inside the Fontainebleau Miami Beach with a hydrotherapy circuit, mineral pools and a eucalyptus steam room, open to hotel guests booking

Indianapolis, Indiana

Day spa in Allisonville, Indianapolis with sauna, steam room, thermal pool and cold plunge, plus about 10 massage and facial treatments for solo visits or

Monroe, Utah

Natural hot spring pools fed by mineral water in rural Monroe, Utah, open 24/7 with day-pass soaking and funky bus and cabin lodging on site.

Scottsdale, Arizona

North Scottsdale day spa with massage, facials, sauna, steam and a thermal pool, plus private suites for couples and groups.

Hobart, Tasmania

Upscale day spa in central Hobart with infrared sauna, magnesium spa, ice bath and in-house naturopathy, open daily except Mondays with walk-ins and day passes.

Riviera Maya, Quintana Roo

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.

Santa Fe, New Mexico

A 77-acre hot springs resort outside Santa Fe with spring-fed thermal pools, day-pass soaking packages from $175, and overnight lodging.

Los Angeles, California

Women-only Korean day spa in Koreatown, LA with saltwater, mineral and cold pools, a salt room, and walk-in day passes.

Scottsdale, Arizona

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.

Mornington Peninsula, Victoria

Geothermal hot springs and day spa in Fingal on the Mornington Peninsula, with a family-friendly Bath House and an adults-only Spa Dreaming Centre.

Hudson, New York

Adults-only communal thermal baths and steam room in downtown Hudson, NY, with day passes, memberships and treatment-plus-soak packages.

Park City, Utah

A 14-room hotel spa at Westgate Park City Resort with a waterfall, sauna, steam room and thermal pools, open daily 9:30am-6:30pm.

Naples, Florida

Luxury day spa in Central Naples offering massage, facials and combination packages, including a $420 signature ritual, with couples treatments by reservation.

Hot Springs, Arkansas

Thermal-water bathhouse on Central Ave in Hot Springs offering soaking pools, private mineral baths and eight spa treatments, minimum age 14.

Aspen, Colorado

Adults-only hotel spa at The St. Regis Aspen with Thai-inspired massage, 111Skin facials, an AI robotic massage, and a day pass covering pool, cold plunge, and

Boston, Massachusetts

Hotel spa inside Raffles Boston pairing Guerlain facials and massages with a 65-foot lap pool, hot tub, sauna, steam room and three private treatment suites.

Lombok, West Nusa Tenggara

A hotel-guest-only wellness room at Rascals in Kuta, Lombok, with a traditional sauna, dual ice baths and a magnesium pool, open daily 8am–9:30pm.

Scottsdale, Arizona

A hotel spa at JW Marriott Desert Ridge with sauna, steam rooms, a sanctuary pool, bistro and salon, open to day-pass guests as well as hotel guests.

Park City, Utah

Hotel spa in Canyons Village at the Grand Summit with sauna, steam room, three whirlpools and a 22-treatment menu including ski-recovery massages.

Denver, Colorado

Bathhouse in Denver's Ballpark District built around contrast therapy: a 40-person cedar sauna, eucalyptus steam room, five cold plunges, and thermal soaking

Saratoga Springs, New York

Historic 1935 bathhouse in Saratoga Springs offering mineral water soaks and massages in original tubs, reservation only, moderate pricing.

Busan

A large Korean jjimjilbang inside Centum City with 18 hot spring baths and 13 themed heat rooms, open daily 9am–10pm.