Spas with moderate

Seattle, Washington

A quiet, clothing-optional day spa in Greenwood with soaking pools, saunas and a steam room, women-owned and open to all genders on Wednesdays.

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.

Denver, Colorado

A 6,000-square-foot hotel spa in downtown Denver's Granite Tower, open to day-pass visitors 18 and older for $40 to $75.

New York City, New York

Korean jjimjilbang-style spa in Manhattan with saunas, steam room, soaking tub and body scrubs, open daily 8am-11:30pm on a day-pass basis.

BAITING HOLLO, New York

A 10,000-square-foot spa and hair salon in Baiting Hollow with couple's suites, saunas and steam rooms, part of the East Wind resort on Long Island.

Denver, Colorado

A hotel spa in downtown Denver with a $150 day pass covering pool, steam room, whirlpool and fitness centre access, open to non-guests.

Vail, Colorado

A day spa and recovery club in downtown Vail with hot tub, sauna, steam room, cold plunge and salt lounge, plus day passes and fitness access.

Hanmer Springs, Canterbury

Day spa in Hanmer Springs offering massages and facials, with some packages including access to the thermal pools complex next door.

Las Vegas, Nevada

Hotel spa on the Palms casino level in Las Vegas with steam rooms, saunas, a seasonal pool and 32 treatments including massage, facials and body work.

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.

Ho Chi Minh City

A Korean-style jjim jil bang in Ho Chi Minh City with six heated rooms, a Dead Sea mineral soaking pool, and massage, hair-wash and facial services.

Pagosa Springs, Colorado

Hot springs resort in Pagosa Springs, Colorado, built around the geothermal Mother Spring, open daily for day-pass soaking or overnight stays.

Aspen, Colorado

Adults-only hotel spa at Viewline Resort Snowmass with a $25 day pass, steam rooms, outdoor pool and whirlpool, reservations required.

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.

Spa, Liège

Thermal baths in the town of Spa, Belgium, fed by natural mineral water, with saunas, hammams and separate textile and naturist relaxation areas.

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.

Cedar Park, Texas

Cedar Park float spa offering sensory-deprivation float therapy plus sauna, steam room and cold plunge, open daily 8am-10pm.

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.

Chicago, Illinois

A Near South Side day spa pairing Chinese-technique massage and foot reflexology with a wine and cocktail menu, priced for couples visits.

Hanoi

Day spa in Hanoi's Old Quarter with a herbal steam room, Himalayan salt stone room and jacuzzi, open daily 10am–10pm.

Los Angeles, California

Day spa in West Hollywood with wet and dry banyas, pool, sauna, cold plunge and café; day pass is $110, walk-ins welcome.

Taupo, Waikato

Adults-only geothermal hot springs in the Wairakei valley near Taupo, with three thermal pools fed by natural silica-rich mineral water, plus spa treatments