Spas with thermal pool

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.

Pagosa Springs, Colorado

Victorian-style bathhouse in downtown Pagosa Springs with mineral soaking tubs, a rooftop tub, sauna, cold plunge and on-site massage.

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.

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

Seattle, Washington

A clothing-optional outdoor hot pool, sauna and sun deck in Seattle's West Woodland, open to walk-ins for three-hour day visits.

Scottsdale, Arizona

Hotel spa at the Inn at Eagle Mountain in Fountain Hills with sauna, steam room, pools and a $69 60-minute massage as its signature treatment.

Las Vegas, Nevada

Adults-only hotel spa inside Westgate Las Vegas offering massages, facials, salon services, sauna, steam room and a thermal pool, open daily 9am-6pm.

Vail, Colorado

Hotel spa at the Westin Riverfront in Avon near Vail, with 14 treatment rooms, a saline lap pool, three infinity hot tubs and day passes for non-guests.

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.

Park City, Utah

A 27-room resort spa at Montage Deer Valley in Park City, open to hotel guests with a pool, steam room, sauna and cold plunge.

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.

Napa Valley, California

Adults-only resort spa built into a wine cave in Napa, with a vineyard-view pool, sauna, steam room and hot tub; reservations required.

San Diego, California

Adults-only hotel spa at Kona Kai Resort on Shelter Island with six treatment rooms, a couples' suite and day-pass access for non-guests.

Tucson, Arizona

Adults-only hotel spa at El Conquistador Tucson with a salt therapy lounge, heated outdoor pool and mountain views, day passes available to hotel guests.

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

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.

Marana, Arizona

Adults-only hotel spa at Dove Mountain Resort in Marana with desert-themed treatments, an infinity-edge pool, sauna and steam room; facility access comes with

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.