Spas with thermal pool

New York City, New York

Korean-style day spa in Edgewater, NJ, with saunas, thermal pools and an infinity pool, open daily 9am–9:30pm, day passes for walk-ins.

Austin, Texas

Adults-only hotel spa at the Fairmont Austin with nine treatment rooms, a hydrotherapy circuit, sauna and cold plunge, open daily with day passes available.

New York City, New York

A budget-friendly Korean-style bathhouse in Queens with indoor and outdoor hydrotherapy pools, saunas and a restaurant, open to walk-ins daily.

Dallas, Texas

Korean-style day spa in Carrollton with hydrotherapy pools, saunas and relaxation lounges, open daily 9am–9:30pm with walk-in day passes.

Boca Raton, Florida

Hotel spa at The Boca Raton with 44 treatment rooms, a spa pool and waterfall whirlpools, open to resort guests, club members and day-pass visitors by

Park City, Utah

Hotel spa at Pendry Park City with six treatment rooms, a rooftop pool, whirlpool and herbal steam room, open daily 8:30am–4:30pm.

Palm Springs, California

Adults-only hotel spa at Tommy Bahama Miramonte in Indian Wells with 15 treatments, eucalyptus steam rooms, a hydrotherapy jacuzzi and saltwater pool.

Tuscany

A five-star resort in the Tuscan countryside built around a natural thermal spring, with day passes from €39 for outdoor thermal pools, hydromassage circuits

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.

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.

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.

San Diego, California

Adults-only day and hotel spa in Rancho Bernardo with gardens, whirlpools, a steam room and an 18-treatment menu, open daily 9am-6pm.

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

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.

The Colony, Texas

A day-soaking spa in The Colony with mineral pools at varying temperatures, seven saunas, cold plunges and a poolside café.

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.

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.

Koh Samui, Surat Thani

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

Chicago, Illinois

Upscale day spa in Lincoln Park, Chicago, where booking any treatment unlocks all-day access to a hydrotherapy circuit, thermal suite and outdoor terrace.