Spas with outdoor baths

Bagno Vignoni, Tuscany

Hotel spa in a 15th-century Bagno Vignoni palazzo with a thermal pool fed by the village's natural hot springs, open to day visitors.

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.

Calistoga, California

A moderate-priced resort spa in Calistoga with geothermal mineral pools, open daily 9am-5pm and offering day passes to the public.

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.

Opatija, Primorje-Gorski Kotar

A 5-star hotel spa in Opatija with a sauna centre, seawater pools and couples treatments, open only to Hotel Ambasador guests.

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.

Archena, Murcia

A 19th-century thermal hotel in Archena with direct access to a Roman-era spring complex, open to day visitors as well as overnight guests.

Ein Bokek, Southern District

Hotel spa on the Dead Sea shore in Ein Bokek with a heated mineral-water pool, sulphur pools, hammam and sauna; day passes open to adults 16 and up.

Windermere, England

Resort hotel spa on Lake Windermere's shore with thermal suite, indoor pool, sauna and steam rooms, plus massage and facial treatments.

Santa Fe, New Mexico

A 77-acre hot springs resort outside Santa Fe with spring-fed thermal pools, day-pass soaking packages from $175, and overnight lodging.

Archena, Murcia

Thermal spa resort in Archena, Murcia, with a 3,000m² thermal circuit, outdoor baths and a day pass from €23.

Auckland

A family-run rainforest resort in the Waitakere Ranges near Auckland offering a day spa, private yoga and free hiking and biking trails.

Hunter Valley, New South Wales

A resort spa inside Avani Cypress Lakes in Pokolbin, open to hotel guests for treatments, thermal pools, outdoor baths and a fitness and yoga space.

Calistoga, California

A 1952 Calistoga hot springs resort with three mineral pools at 85, 95 and 104°F, mud baths, overnight rooms and a day-pass option.

Sedona, Arizona

A resort spa at Amara in Sedona with outdoor baths, an infinity pool and a relaxation lounge, open only to hotel guests.

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.

Puyehue, Los Lagos

A forest resort spa in Puyehue, Chile, with volcanic thermal pools and outdoor baths, open only to hotel guests.

Dallas, Texas

A hotel spa at Omni Las Colinas in Irving, Texas, with an outdoor pool and bath area, open to hotel guests along Lake Carolyn.

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.

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.

East End, St. Thomas

Hotel spa inside a 30-acre oceanfront Ritz-Carlton resort on St. Thomas's East End, with a $450 day pass for pool and outdoor bath access.

Tucson, Arizona

A hotel spa at an 80-acre Sonoran Desert resort in Tucson, open to overnight guests, with three pools, hot tubs, sauna and yoga classes.

Nha Trang, Khanh Hoa

A resort spa on a private peninsula near Nha Trang, open only to guests staying at the 37-villa An Lam Retreats.