Spas with hotel guests only

Hua Hin, Prachuap Khiri Khan

Hotel spa at The Standard, Hua Hin, offering 11 treatments, ice bath therapy, and a day pass option at a beachfront resort on Naresdamri Road.

Miami, Florida

Adults-only hotel spa on Belle Isle near South Beach with a hammam, sauna, ice room, infinity pool and a day pass option for non-guests.

Philadelphia, Pennsylvania

Hotel spa in Center City Philadelphia with a heated indoor saltwater pool, fitness center and day-pass access for non-guests.

Dax, Nouvelle-Aquitaine

Family-run thermal hotel in Dax with a supervised pool, sauna, hammam and a 20-treatment mini-cure over five days, plus day-pass access to the spa.

San Pedro de Atacama, Antofagasta

A hotel spa inside the luxury Tierra Atacama lodge near San Pedro de Atacama, with indoor and infinity pools, sauna, steam room and treatment rooms, open only

Palm Springs, California

A 16-room adults-only hotel in Desert Hot Springs with three natural mineral-water pools fed by a 350-foot geothermal well, plus a small on-site spa and

Rogaška Slatina, Savinjska

Wellness center at Grand Hotel Rogaška in Rogaška Slatina, Slovenia, with pools, saunas and fitness; day pass available by reservation.

Bled, Upper Carniola

Hotel spa at Bled's Rikli Balance Hotel with six pools, six saunas and lake views, open to hotel guests only.

Yalova

Historic Ottoman-era thermal baths in Yalova's Termal district, with day-pass access to pools and private bath cabins.

Orlando, Florida

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

Miami, Florida

Hotel spa inside the InterContinental Miami, open daily with a day pass option, 11 treatments and a signature Raindrop Massage.

Vals, Grisons

Peter Zumthor's quartzite thermal baths in Vals, built into the mountain, open to day visitors as well as hotel guests.

Bridgetown, Christ Church

Hotel spa at Accra Beach Hotel in Christ Church, Barbados, with six treatment rooms, a sauna and steam room, open daily 8am-7pm for hotel guests.

Amalfi Coast, Campania

Hotel spa inside a former 13th-century monastery in Amalfi, with hammam, couple rooms and sauna, open to guests only.

Hunter Valley, New South Wales

A resort spa inside Avani Cypress Lakes in Pokolbin, open to hotel guests for treatments, thermal pools, outdoor baths and a fitness and yoga space.

Puerto Vallarta, Jalisco

A hotel spa inside the beachfront Buenaventura Grand Hotel in Puerto Vallarta, open to resort guests for massage and relaxation between beach days.

Osprey, Florida

Hotel spa and pool deck at a moderate-price resort in Osprey, Florida, with sauna, steam room and thermal circuits for overnight guests.

Calistoga, California

A 1952 Calistoga hot springs resort with three mineral pools at 85, 95 and 104°F, mud baths, overnight rooms and a day-pass option.

Banff, Alberta

Luxury hotel spa inside Fairmont Banff Springs offering thermal pools, steam rooms and treatments, open daily with day passes for non-guests.

Ginzan Onsen, Yamagata

A riverside hotel spa in Ginzan Onsen with a thermal bathing pool, overnight stay and day-pass access for non-guests.

Scottsdale, Arizona

Hotel spa at the mid-century Hotel Valley Ho in South Scottsdale, with sauna, steam room and two pools, open to hotel guests only.

Hilton Head Island, South Carolina

Hotel spa inside an oceanfront Hilton Head resort, offering massages, facials, body treatments and manicures to overnight guests.

Mariánské Lázně, Karlovy Vary Region

Medical spa resort in Mariánské Lázně combining balneology, physiotherapy and Ayurveda programs, open only to overnight hotel guests aged 18+.

Brežice, Posavje

A large thermal water park in Brežice, Slovenia, with a year-round indoor pool riviera, an adults-only sauna zone, and seasonal outdoor slides.