Spas with thermal pool

Chicago, Illinois

Thermal baths and spa rituals in a restored 1902 factory in West Town, Chicago, open daily for adults-only soaking and massage packages.

London, England

Thermal bathhouse near Covent Garden in a former J.M. Barrie house, offering multi-temperature pools, massages and couples treatments by reservation.

Toronto, Ontario

A reservation-only thermal bath circuit in a 1912 Edwardian building in Toronto, with eight pools, a dry sauna, steam room and massage treatments.

Barcelona, Catalonia

Adults-only thermal baths in a converted 18th-century building near Barcelona's Born market, with soaking pools, massages and couples rituals.

Copenhagen, Capital Region

A thermal-bath spa in Vesterbro, Copenhagen, built around a signature Pediluvium foot-bath ritual plus a relaxation lounge and thermal pool.

Amman

A hotel hammam in Tla al-Ali, Amman, with marble bathing halls, a hot pool, sauna and Jacuzzi, offering about 20 treatments from a basic scrub to a $120

Bad Gastein, Salzburg

Thermal baths in Bad Hofgastein with indoor/outdoor pools, bathing lakes, slides, saunas and a sports medicine center, open daily year-round.

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.

Saint-Malo, Brittany

A three-in-one day spa in Saint-Malo combining a salt-water aquatic circuit, spa treatments and a fitness club, open daily on a day-pass basis.

Washington, D.C., District of Columbia

A multi-level day spa near DC with indoor and rooftop hydrotherapy pools, several sauna types, lounges, an a la carte spa menu and eateries.

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.

Miami, Florida

Day spa in the Sherry Frontenac Hotel's lower lobby in Miami Beach, with sauna, steam, cold plunge and thermal pool alongside massage treatments.

Kuala Lumpur

An onsen-style day spa in Kampung Baru, Kuala Lumpur, with thermal pools, sauna, steam room and couples treatments.

Hammamet, Nabeul

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

Houston, Texas

A Houston day spa near Memorial Park focused on massage and bodywork, with a spa pool, sauna and outdoor retreat, open daily 10am-8pm.

Napa Valley, California

A boutique day spa in downtown Napa Valley with nine treatment rooms offering massage, facials and body work, plus sauna, steam and a thermal pool.

Scuol, Grisons

A year-round thermal bathing complex in Scuol with indoor-outdoor mineral pools, a brine pool, cold and warm grottos, and a fireside lounge.

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.

Plainfield, Indiana

Day spa in Plainfield, IN offering facials, massages and body-sculpting treatments alongside a sauna, steam room and thermal pool, reservation required.

Baden-Baden, Baden-Württemberg

Modern thermal baths in Baden-Baden with indoor-outdoor pools and a Roman-style sauna garden, open daily 8am–10pm, day pass €40.

Prague

A day spa near Wenceslas Square in Nové Město offering massages, facials and thermal pool access with day passes for walk-ins.

Quito, Pichincha

A family-friendly day spa in Conocoto, just outside Quito, with a thermal pool and a $16 day pass, open daily from 9am to 9pm.

Da Nang

A Korean-style bathhouse and onsen complex in Da Nang's Hoa Xuan area, with hot spring baths, 11 sauna rooms, massage and a riverside restaurant.

Strongsville, Ohio

Membership-style wellness studio in Strongsville with sauna, steam room and thermal pool, plus a $49 unlimited day pass for first-time visitors.