Spas with walk-ins welcome

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.

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.

Las Vegas, Nevada

Adults-only hotel spa at Resorts World Las Vegas with a six-pool hydrotherapy circuit, salt room, and a themed Aufguss sauna show on weekends.

Hammamet, Nabeul

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

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.

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.

Florence, Tuscany

A 650-square-meter spa inside a 14th-century Florence monastery, with thermal pool, guesthouse rooms, bistro and day-pass access.

Las Vegas, Nevada

Hotel spa inside Hilton Grand Vacations on the Las Vegas Strip, open to non-guests via day pass or booked treatment, minimum age 16.

Eger, Heves

Outdoor thermal bath complex in Eger with sulfurous and radon medicinal pools, family pools and a slide pool, open daily from 9am to 7pm.

Pärnu, Pärnu County

Thermal bath complex in Pärnu with pools, saunas and hot tubs, open daily 7:30–21:30, day passes from €15 on weekdays.

Bad Füssing, Bavaria

Large thermal bath complex in Bad Füssing with 17 indoor and outdoor pools, a sauna area and therapy basins, open daily year-round.

Hajdúszoboszló, Hajdú-Bihar

A medical thermal bath in Hajdúszoboszló, Hungary, with iodine-bromine-salt water pools treating rheumatic and joint conditions, open daily 7am–7pm.

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.

Zurich

Thermal baths and rooftop infinity pool set in a former Zurich brewery's historic vaults, with a Roman-Irish spa ritual and day-pass access.

Wiesbaden, Hesse

A 16+ textile-free thermal bath in central Wiesbaden with Roman-style architecture, saunas, steam rooms and a cold plunge pool.

Bad Kissingen, Bavaria

Thermal bath and sauna park in Bad Kissingen with 10 indoor/outdoor pools, nine saunas and a day pass around €40.

Florence, Tuscany

Hotel spa inside the Helvetia & Bristol in central Florence, with two heated pools, a calidarium, sudatorium and tepidarium, open daily to walk-ins and hotel

Tucson, Arizona

Hotel spa at Omni Tucson National Resort with 12 treatment rooms, a couples suite, salon services, and day passes open to both guests and locals.

Munich, Bavaria

A Jugendstil bathhouse from 1901 in Haidhausen with two swimming halls, a Roman-Irish steam bath and sauna, day pool pass from €5.80.

San Juan

Adults-only boutique hotel in San Juan's Santurce/Condado area with a rooftop indoor plunge pool, private suites and a signature couple's massage, priced at