Spas with thermal pool

Hot Springs, Arkansas

Historic 1924 thermal bathhouse inside the Arlington Hotel in Hot Springs, offering mineral baths, sauna and massage, with walk-ins welcome.

Taos, New Mexico

Hotel day spa at El Monte Sagrado in Taos with a hydrotherapy circuit, saltwater pool and treatment rooms, open daily, day passes available.

Scottsdale, Arizona

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.

Lake Tahoe, California

A 17-room, adults-only hotel spa at Lake Tahoe's Ritz-Carlton with a heated lap pool, sauna and steam room; day pass access requires booking a treatment.

Naples, Florida

Hotel spa at The Ritz-Carlton, Naples with 23 treatments, steam rooms, plunge pool and separate men's and women's lounges, open daily 9am–6pm.

Naples, Florida

A hotel spa at Naples Beach Club with a 3,200-square-foot thermal circuit, rooftop lap pool and body/facial treatments built around ocean and plant themes.

Los Angeles, California

Four Seasons hotel spa in Beverly Hills with a steam room, rooftop pool, fitness center and eight treatments, open daily, day passes available.

Palm Springs, California

A 38,000-square-foot resort spa at JW Marriott Desert Springs in Palm Desert offers day passes, saunas, a saltwater lap pool and couples suites.

Atlanta, Georgia

Hotel spa inside the Four Seasons Atlanta in Midtown, open to guests 16 and up for massages, facials and a heated saline pool with sauna and steam room.

Vail, Colorado

A hotel spa at Grand Hyatt Vail with three treatments, an outdoor heated infinity pool, hot tubs and cold plunges along Gore Creek.

Bodrum, Muğla

Adults-only hotel spa at Mandarin Oriental, Bodrum with sauna, steam, cold plunge and thermal pools, open daily 10am-10pm, reservation required.

Killarney, Munster

Hotel spa and leisure studio at The Killarney Park with a 20m pool, outdoor jacuzzi, sauna and steam room, open to hotel guests only.

Asheville, North Carolina

Adults-only hotel spa in Asheville with a fiber-optic-starred lap pool, waterfall pools, saunas and an electronics-free policy; day passes are limited and

Galway, Connacht

Adults-only hotel spa in Galway with a thermal suite, hydro pool and sauna; day pass runs about €50 and reservations are required.

Calistoga, California

A 20-treatment hotel day spa in Santa Rosa with an indoor caldarium plunge pool, eucalyptus steam rooms, and walk-in or reserved day passes for adults 18+.

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.

Whistler, British Columbia

Hotel spa at the Westin in Whistler Village with 19 treatments, couples massage, and free access to the hotel's pools, sauna, steam room and gym.

Bath, England

Adults-only thermal spa in central Bath with a naturally warm mineral rooftop pool, open daily 9am–9pm with walk-in day passes.

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

Gold Coast, Queensland

A 90-minute hydrotherapy circuit in Southport with a Finnish rock sauna, 5° ice baths and hot/cold magnesium pools, day pass $49.

Bled, Upper Carniola

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

Galle, Southern Province

Oceanfront hotel spa at Radisson Collection Resort Galle, open daily 9am-9pm with walk-ins, sauna, steam, pools and Ayurvedic treatments from $65.

Palm Springs, California

Adults-only clothing-optional resort in Desert Hot Springs with mineral water pools, whirlpools, a nude cedar sauna and day-pass access.

Wulai, New Taipei

A hilltop Wulai B&B with sodium bicarbonate hot-spring baths in every room and an outdoor infinity pool, geared toward couples.