Spas with hotel guests only

Las Vegas, Nevada

Adults-only hotel spa inside ARIA Resort & Casino in Las Vegas, with sauna, steam room, thermal pools and cold plunge, open to hotel guests 18 and up.

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.

Bagno Vignoni, Tuscany

Hotel spa in a 15th-century Bagno Vignoni palazzo with a thermal pool fed by the village's natural hot springs, open to day visitors.

Santiago, Santiago Metropolitan

A hotel spa in Macul, Santiago, with thermal pools, sauna, steam room and cold plunge, open to hotel guests only, no day passes offered.

Längenfeld, Tyrol

A large thermal bath and 4-star hotel spa in the Ötztal valley near Längenfeld, with indoor-outdoor pools, a sauna garden and a dedicated kids' water world.

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.

Tenerife, Canary Islands

A hotel spa at Bahía del Duque in Costa Adeje with an outdoor seawater thalassotherapy circuit, hammam, saunas and a cold plunge, open to day visitors.

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.

Doha

Hotel spa inside Banyan Tree Doha with separate men's and women's hydrothermal suites, open daily 10am-11pm to hotel guests only.

Karlovy Vary, Karlovy Vary Region

A 5-star medical spa and wellness hotel beside Karlovy Vary's colonnades, with seven saunas, five pools and a day pass for non-guests.

San Francisco, California

A hotel spa at Fort Baker near Sausalito for Cavallo Point guests, with a meditation pool, Zen garden, infrared sauna and outdoor Jacuzzis.

Riviera Maya, Quintana Roo

Adults-only hotel spa at Devossion by Live Aqua in Playa del Carmen, open daily 8am-8pm, with sauna, steam room and pools for resort guests.

Chicago, Illinois

Adults-only hotel spa in River North with a 67-foot pool, multiple sauna and steam rooms, and day passes for non-guests.

Stockholm, Stockholm County

A hotel spa on Södermalm with indoor and outdoor pools, a dry sauna and a steam room, open to day-pass visitors aged 16 and up.

Miami, Florida

Hotel spa inside Dua Miami, Autograph Collection in Brickell, open daily 9am-6pm, with sauna, steam room, cold plunge and couples massage rooms.

Montego Bay, Saint James

A 12-treatment hotel spa at Half Moon resort in Montego Bay, with a waterfall-fed lagoon pool, steam rooms and outdoor yoga, open to resort guests only.

Tuscany

Hotel spa inside Florence's Four Seasons, with a walled garden pool, whirlpool, sauna, steam room and couples suite, open to day-pass guests.

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.

Tucson, Arizona

A resort spa in Tucson's Starr Pass area with a saline lap pool, sauna and fitness center, plus signature treatments from $159 for hotel guests.

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.

Opatija, Primorje-Gorski Kotar

A 5-star hotel spa in Opatija with a sauna centre, seawater pools and couples treatments, open only to Hotel Ambasador guests.

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.

Valle de Bravo, State of Mexico

A forest hotel spa outside Valle de Bravo built around a hydrotherapy circuit of hammam, sauna, cold pool and contrast pools, open to overnight guests only.

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.