Spas with hotel guests only

Palm Springs, California

Hotel spa at the Grand Hyatt in Indian Wells with sauna, steam room, cold plunge and five treatment options for solo guests or couples.

Las Vegas, Nevada

Co-ed hotel spa at W Las Vegas with sauna, steam room and cold plunge, open to hotel guests only with day passes from $75.

O Grove, Galicia

A thermal spa on Isla de la Toja combining a seawater hydrotherapy circuit with a mineral-medicinal water balneario, open daily with a day pass option.

Palm Springs, California

Moroccan-themed inn in Desert Hot Springs with natural mineral hot springs, a spring-fed pool and day-pass access from 9am to 4pm.

Vail, Colorado

Hotel spa and recovery club in Vail Village with hot tubs, cold plunge, sauna, salt room and a gym, open to day-pass visitors.

Doha

Hotel spa at The Westin Doha with some of the city's largest wet facilities, accessible to hotel guests and members only, no day passes sold.

Krynica-Zdrój, Lesser Poland

Mountain resort spa in Krynica-Zdrój with indoor and outdoor pools, a sauna complex, and a clothing-optional 18+ zone; day passes available.

Velingrad, Pazardzhik

Hotel spa in Velingrad with mineral-water pools, saunas, steam rooms and a hammam spread over 4,000 square metres; day passes are available.

Bursa

A historic thermal bathhouse and small hotel in Bursa's Kükürtlü district, with separate men's and women's hamams, day passes, and overnight stays.

Orlando, Florida

Family resort near Walt Disney World with a pirate-themed pool complex and a spa offering day passes and couples treatments.

Ein Bokek, Southern District

Hotel spa on the Dead Sea shore in Ein Bokek with a heated mineral-water pool, sulphur pools, hammam and sauna; day passes open to adults 16 and up.

Pärnu, Pärnu County

A 193-room medical spa hotel in Pärnu with a pool and sauna complex, salt therapy, physiotherapy and water aerobics, open to day visitors.

Scuol, Grisons

Hotel spa at the 4-star Belvedere in Scuol with indoor/outdoor pools, mineral and thermal water, sauna, steam bath and a day pass option.

Vail, Colorado

Hotel spa inside the Sonnenalp Resort in Vail with indoor-outdoor pools, whirlpools, an oxygen bar and $50 day passes when space allows.

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.

Chamonix, Auvergne-Rhône-Alpes

Hotel spa at Heliopic Chamonix with an ice cave, cold-water well, hammams, sauna and a 15m pool facing the Mont Blanc massif, open to day visitors who book a

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

Mendocino, California

A redwood hot tub and sauna spa in Mendocino village, offering massage and private soaks mainly for guests of the adjoining Sweetwater Inn.

Santa Barbara, California

A 42,000-square-foot hotel spa in Santa Barbara with an adults-only pool, redwood sauna, eucalyptus steam room, cold plunge and rooftop terrace.

Los Angeles, California

Downtown LA hotel spa at the Ritz-Carlton with massages, facials, a couples suite, rooftop pool and gym; outside guests need to book a treatment to enter.

Calistoga, California

Hotel spa in downtown Healdsburg with a garden patio, jacuzzi and pool access, open daily 9am-5pm for guests and day visitors.

Chicago, Illinois

A hotel spa inside Four Seasons Chicago, Streeterville, with an indoor infinity-edge pool, whirlpool and fitness centre, open on a day-pass basis.

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.

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.