Spas with thermal pool

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.

Amsterdam, North Holland

A day spa inside a former bank vault in central Amsterdam, with pool, whirlpool and a canal-view gym; adults-only, day pass by reservation.

San Francisco, California

Adults-only Russian bathhouse in San Francisco's India Basin with steam rooms, cold plunge, rooftop deck and a café, open daily except Tuesday.

Hot Springs, Arkansas

Adults-only hotel spa at Oaklawn Resort in Hot Springs with vitality pools, heated loungers, needle showers and treatment-based access only.

Palm Springs, California

Adults-only hot springs resort on Miracle Hill in Desert Hot Springs with private mineral tubs, a Finnish sauna, salt room and 35 spa treatments.

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.

Doha

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

Hammamet, Nabeul

Seafront thalasso spa in Hammamet Est with a thermal pool, 42 treatments, and day passes open daily from 8am to 7pm.

Bormio, Lombardy

Family-friendly thermal baths in Bormio with chlorine-free pools heated to 37–40°C, plus sauna, steam room and adult-only wellness areas.

Miami, Florida

A beachfront resort spa in North Beach, Miami with cryotherapy, a floating salt bath, sauna, steam and a cold plunge, open to walk-ins and day-pass guests.

Los Angeles, California

A Korean spa in Arlington Heights, LA, with gender-separated floors, a co-ed Jim Jil Bang, pool and body scrubs; open daily 9am–midnight.

Marrakech, Marrakesh-Safi

A 1,200-square-metre hotel spa at Selman Marrakech built around the Chenot method, with hammams, pools and multi-day wellness programmes.

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.

Durango, Colorado

A hot springs resort in the Animas Valley near Durango, Colorado, with 32 mineral pools, cold plunges, a lap pool and private cedar soaking tubs.

Vail, Colorado

Adults-only day spa at The Charter at Beaver Creek with saltwater pools, steam room, sauna and a day pass for treatments or facility access.

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.

Scottsdale, Arizona

Adults-only hotel spa at The Scott in Scottsdale with six treatment rooms, sauna, steam and pools, plus day passes for non-guests.

Tucson, Arizona

Hotel spa at Loews Ventana Canyon Resort, Tucson, with eight treatment rooms, an adults-only pool, and a 24-hour fitness center; open daily 9am–6pm.

Miami, Florida

Adults-only hotel spa inside the Fontainebleau Miami Beach with a hydrotherapy circuit, mineral pools and a eucalyptus steam room, open to hotel guests booking

Phuket

Adults-only Ayurvedic resort on a Rawai hillside with doctor-led Panchakarma programs, a saltwater pool and 47 private villas.

Munich, Bavaria

A Jugendstil bathhouse from 1901 in Haidhausen with two swimming halls, a Roman-Irish steam bath and sauna, day pool pass from €5.80.

Längenfeld, Tyrol

A 1,800 m² wellness spa inside an adults-only hotel in Austria's Ötztal valley, with sauna, outdoor pool and treatment rooms for guests only.

Riviera Maya, Quintana Roo

Adults-only spa inside the all-inclusive Ocean Riviera Paradise resort in Playa del Carmen, with sauna, Turkish bath and four treatment options via day pass.

Edinburgh, Scotland

One Spa is an adults-only day spa in Edinburgh's city centre with a rooftop Hydropool, thermal suite and day-pass access.