Spas with overnight stay

Băile Herculane, Caraș-Severin

Hotel-based thermal spa in Băile Herculane with sulfur mineral baths, indoor and outdoor pools, jacuzzi and sauna, open to hotel guests.

Ubud, Bali

An adults-only wellness retreat on Ubud's Ayung River offering multi-day healing programmes, thermal circuits and plant-based cuisine by reservation only.

Băile Herculane, Caraș-Severin

A 4-star hotel in central Băile Herculane with thermal pools, saunas, balneo and physiotherapy treatments, open to overnight guests.

Leukerbad, Valais

A 30-room hotel in Leukerbad with a private thermal pool and sauna chalet, open to overnight guests only, overlooking the Gemmi massif.

Tucson, Arizona

Lakeside Spa at this 398-room desert resort in Tucson is open to hotel guests only, with two heated pools, a Jacuzzi and mountain views of Catalina range.

Hudson Valley, New York

Day spa near Wallkill and Gardiner in the Hudson Valley offering massage, skincare and energy-healing treatments, with an on-site bed and breakfast for

Kurokawa Onsen, Kumamoto

Okunoyu is a ryokan onsen in Kurokawa Onsen, Kumamoto, with outdoor thermal baths open to day visitors and overnight guests, daily 8:30am–8:30pm.

Bad Ischl, Upper Austria

A salt-and-brine thermal bath complex in Bad Ischl with indoor/outdoor pools, a sauna world, and a rooftop wellness deck at the attached hotel.

Kandy, Central Province

An adults-only Ayurvedic retreat in the hills above Kandy, Sri Lanka, with overnight stays, yoga and a restaurant, but no day-pass access.

Fort Lauderdale, Florida

Hotel spa at The Atlantic Resort on Fort Lauderdale Beach with sauna, steam room, cold plunge and thermal pool, for overnight guests only.

Scottsdale, Arizona

Hotel-guests-only spa at Scottsdale's Kimpton Miralina, with sauna, cold plunge and desert-inspired massages, mud wraps and facials.

Coorg, Karnataka

A luxury coffee-plantation resort in Coorg with a spa and pool facilities reserved for overnight guests.

Baden bei Wien, Lower Austria

A thermal bath in Bad Vöslau with four mineral-water pools fed by the original Vöslauer spring, plus sauna and steam room.

Leukerbad, Valais

Thermal baths inside a 19th-century hotel in Leukerbad, Valais, with mineral-rich pools open daily from 9am to 8pm.

Vals, Grisons

Peter Zumthor's quartzite thermal baths in Vals, fed by a 30°C mineral spring, open to day visitors as well as hotel guests.

Solvang, California

A resort spa inside Alisal Ranch, a 10,500-acre luxury guest ranch in Santa Ynez Valley open only to overnight guests by reservation.

Carmel-by-the-Sea, California

A resort spa inside Bernardus Lodge in Carmel Valley wine country, open to lodge guests for treatments, yoga and a relaxation lounge.

Mendocino, California

A bluff-top inn on the Mendocino coast offering massages, yoga and sound therapy to overnight guests, with meals included.

Hudson Valley, New York

Hotel spa at a small Hudson Valley inn on 75 riverside acres in Milton, NY, open to overnight guests by reservation while the spa undergoes renewal.

Bük, Vas

A medicinal thermal bath complex in Bükfürdő with pools, a sauna area and on-site accommodation, open daily on a day-pass basis.

Portland, Oregon

Adults-only hotel and thermal springs on NE Alberta St in Portland, with vitality pools, a day-pass option, and spa treatments.

Berkshires, Massachusetts

An all-inclusive destination resort in the Berkshires combining spa treatments, fitness, and themed wellness retreats, open daily with reservations required.

Carson, Washington

A clothing-optional, adults-only mineral hot springs bathhouse in Carson, Washington, with a $12 day pass and a $30 bath-and-wrap treatment.

Santa Cruz, California

A hotel spa on a 300-acre Santa Cruz hilltop with Monterey Bay views, outdoor baths and a relaxation lounge, open only to resort guests.