Spas with outdoor baths

Húsavík, Northeastern Region

Geothermal seawater baths built into the cliffs above Skjálfandi bay in Húsavík, with walk-in day passes and views toward the Arctic horizon.

Chicago, Illinois

Upscale day spa in Lincoln Park, Chicago, where booking any treatment unlocks all-day access to a hydrotherapy circuit, thermal suite and outdoor terrace.

Olmué, Valparaíso

A boutique lodge and spa in the Olmué valley, about 80 minutes from Santiago, with a thermal pool, outdoor baths and day passes for non-guests.

Washington, D.C., District of Columbia

Hotel spa at Pendry Washington DC - The Wharf with eucalyptus steam rooms, a heated whirlpool and an outdoor terrace pool, open daily 10am-6pm.

Palm Beach, Florida

Indoor-outdoor luxury spa at The Breakers resort in Palm Beach, open daily 9:30 AM to 6 PM, mainly for hotel guests and club members.

Sonoma, California

Hotel spa at The Lodge at Sonoma with an outdoor terrace, soaking pool, plunge pool and barrel sauna, open daily 9am-5pm, adults-only, reservation required.

Guanacaste, Río Negro

Riverside volcanic hot springs with ten thermal pools and mud baths near Rincón de la Vieja volcano in Guanacaste, Costa Rica.

Rishikesh, Uttarakhand

An upscale riverside resort 18 km outside Rishikesh with an in-house spa, yoga studio and restaurant, open only to overnight guests by reservation.

Mérida, Yucatán

Resort spa on the grounds of Hacienda Xcanatun near Mérida, with a pavilion over a pond offering Asian-style massages and facials by reservation.

Soufrière

Resort spa at Ladera in Soufrière, St Lucia, set between the Pitons with day-pass access to pools, outdoor baths and treatments for couples.

Băile Felix, Bihor

Strand Apollo-Felix is a year-round thermal pool complex in Băile Felix, Romania, with indoor and outdoor pools open daily from 8am to 8pm.

Barcelona, Catalonia

Rooftop day spa at Casa Bonay hotel in Eixample with dry sauna, hammam, ice bath and a Japanese ofuro, booked by small-group circuit or free use.

Hot Springs, Arkansas

A day spa on Central Avenue in Hot Springs with outdoor mineral soaking tubs, cold plunge, infrared sauna, massage and an on-site café.

Scottsdale, Arizona

Adults-only resort spa in Fountain Hills with sauna, steam room and outdoor pools, offering day passes and an amethyst facial as its signature treatment.

Redstone Historic District, Colorado

A ranch property in Colorado's Crystal River Valley with three tiered natural hot springs pools open to day visitors and overnight guests alike.

Valle de Bravo, State of Mexico

An adults-only luxury wellness retreat on the shore of Lake Avándaro in Valle de Bravo, built into a rock formation and run by reservation only.

Beitou, Taipei

A hot-spring resort in Beitou, Taipei with private suites, outdoor baths and overnight stays, open to day-pass visitors by reservation.

Maui, Hawaii

A nine-room resort spa on Maui's Road to Hana offering lomi lomi and lava-stone pōhaku wela massage, plus a eucalyptus steam room and cold plunge.

Kapaau, Hawaii

An oceanfront eco-boutique hotel and wellness retreat on Hawaii Island's North Kohala coast, open to overnight guests only, not day visitors.

Los Baños, Laguna

A natural spring resort near Mount Makiling in Calauan, Laguna, with outdoor pools, forest trails, and day passes offered every day of the week.

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.

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.

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.