Spas with thermal pool

Karjalohja, Uusimaa

Lakeside resort spa on Lohjanjärvi in Karjalohja, about an hour from Helsinki, with a day pass, thermal pool, salt room and restaurant.

San Miguel de Allende, Guanajuato

A Saturday-only hot springs day spa near San Miguel de Allende with outdoor thermal pools and walk-in access.

Miami, Florida

Hotel spa deck in downtown Miami with sauna, steam room, cold plunge and thermal pools overlooking Biscayne Bay, day passes from $50.

Hudson Valley, New York

Resort spa at Mohonk Mountain House with a steam room, sauna and outdoor heated mineral pool, open to overnight guests and day-pass visitors.

Dead Sea, Balqa

Resort spa on the Dead Sea shore with 40 treatments, thermal pools, sauna and steam, open to day guests aged 16 and up.

Montreal, Quebec

A budget-friendly Korean-style spa in Ville-Marie, Montreal with sauna and thermal pool, open to walk-ins.

Asan, South Chungcheong

A hot springs facility in Asan with thermal pools, hot tubs and saunas, open to walk-ins and suited to families.

New York City, New York

Adults-only day spa on Governors Island with heated outdoor pools, saunas and an Italian-style café, reachable by ferry from Manhattan.

Vienna

A day-pass bathhouse on Handelskai in Leopoldstadt with a sauna and thermal pool, open daily 10am–10pm.

Bangkok

Hotel spa at SO/ Bangkok on Sathorn Road offering facial, body and beauty treatments plus rooftop infinity pool and fitness access, hotel guests only.

Shibu Onsen, Nagano

A ryokan in Shibu Onsen with indoor and outdoor hot-spring baths fed by two blended mineral springs, open only to overnight guests.

Scottsdale, Arizona

A luxury resort spa in Paradise Valley near Scottsdale with outdoor baths, a thermal pool and a relaxation lounge, open to hotel guests only.

Scottsdale, Arizona

An adults-only hotel spa in Old Town Scottsdale with sauna, steam room, cold plunge and thermal pools, open to hotel guests 21 and up.

Nashville, Tennessee

A hotel wellness area at Sheraton Music City near Nashville airport, open to guests 21 and up, with sauna, steam room, pools and a whirlpool.

Reykjavik, Capital Region

An oceanfront thermal bath in Kópavogur near Reykjavik, open daily with outdoor pools facing the sea and walk-in day passes.

Tyrol, Bavaria

Hotel spa in Kreuth-Reitrain near Tegernsee with a 3,000 sqm onsen-style bathing area, hot and cold pools, saltwater pools and sauna, open on a day-pass basis.

Jerusalem, Jerusalem District

A hotel spa in Jerusalem with sauna, hot tub and thermal pool, open to walk-ins and day-pass guests most days of the week.

Ourense, Galicia

An outdoor hot-springs spa in Ourense with thermal pools, walk-in day passes, and hours that run late on weekends.

Bath, England

A small open-air thermal pool in a separate building from Thermae Bath Spa's main complex, with its own changing rooms and day-pass access.

Wanaka, Otago

Adults-only hot springs with thermal pool and sauna in Wānaka, open for day passes most evenings and Saturday afternoons, closed Sundays.

Lake Tahoe, California

Hotel-only spa at a lakefront resort in South Lake Tahoe, with an outdoor heated pool, Jacuzzi and treatment rooms aimed at couples.

Miami, Florida

A large hotel wellness resort on North Beach with a European-style hydrotherapy circuit, cryotherapy, acupuncture and an oceanfront fitness center.

Napa Valley, California

Adults-only resort spa in Napa Valley with pools, sauna, steam and a fitness center, open to hotel guests and club members via day pass.

Edinburgh, Scotland

Hotel spa inside The Caledonian on Princes Street with a thermal pool, sauna, steam room and relaxation lounge, open daily 6am to 9pm.