Spas with walk-ins welcome

Nikko, Tochigi

Walk-in public onsen in Nikko with mountain views, a sauna, and a cafeteria, closed Thursdays and open 10am–9pm other days.

St. Moritz, Grisons

An indoor-outdoor pool and spa complex in St. Moritz-Bad with four pools, three slides, a sauna zone, fitness center and bike/Nordic hub under one roof.

Budapest

A centuries-old Turkish-style thermal bath on the Buda riverside with pools, saunas, massages and weekend late-night soaking hours.

Bad Reichenhall, Bavaria

A sole-water thermal bath in Bad Reichenhall with indoor-outdoor pools, an underground salt grotto, sauna area, fitness center and family pool, open daily

Baden bei Wien, Lower Austria

Thermal bath and sauna complex in Baden bei Wien with a sulphur-water outdoor pool and an on-site fitness center, open daily.

Sirmione, Lombardy

A lakeside thermal spa in Sirmione with indoor and outdoor pools fed by sulphurous spring water, a vascular circuit, saunas, and a day-pass option.

Seattle, Washington

A clothing-optional outdoor hot pool, sauna and sun deck in Seattle's West Woodland, open to walk-ins for three-hour day visits.

Sapporo, Hokkaido

Natural hot spring inside Sapporo's Jasmac Plaza Hotel in Susukino, open to day visitors and hotel guests alike, with sauna and a rest lounge.

Arima Onsen, Hyogo

A moderately priced onsen bathhouse in Arima Onsen, Kobe, with a forest sauna, a large outdoor bath, yoga and an award-recognized restaurant.

Sárvár, Vas

Large thermal bath complex in Sárvár with indoor and outdoor pools, a sauna world, slides for kids, and medical spa treatments.

Sárvár, Vas

A large thermal and wellness complex in Sárvár with indoor and outdoor medicinal pools, slides, a sauna world, fitness center and massage treatments.

Ibusuki, Kagoshima

Oceanfront outdoor onsen in Ibusuki where the two gender-assigned baths swap daily, with views of Mount Kaimon, the East China Sea, and Take-yama.

Taupo, Waikato

Adults-only geothermal pool complex in Taupo with five heated pools and a cold plunge, open daily noon to 9pm, no time limit.

Chaves, Norte

Thermal baths complex in Chaves, Portugal, built around natural hot springs, with hydrotherapy, sauna, steam room and massage on a day-pass basis.

Merano, Trentino-South Tyrol

Central thermal bath complex in Merano with 25 pools, a sauna world, thermal park and medical spa area, open daily year-round with walk-in day passes.

Portorož, Coastal-Karst

Thermal baths and seawater pools in Portorož, open daily 7am–9pm with walk-in day passes and a large sauna park.

Hot Springs, Arkansas

Historic 1924 thermal bathhouse inside the Arlington Hotel in Hot Springs, offering mineral baths, sauna and massage, with walk-ins welcome.

Ho Chi Minh City

A Korean-style jjim jil bang in Ho Chi Minh City with six heated rooms, a Dead Sea mineral soaking pool, and massage, hair-wash and facial services.

Bath, England

Adults-only thermal spa in central Bath with a naturally warm mineral rooftop pool, open daily 9am–9pm with walk-in day passes.

Eger, Heves

An indoor-outdoor thermal bath complex in Eger with sulfur and radon pools, a kids' pool, slide pool and adult adventure pool, open daily 10am-6pm.

Spa, Liège

Thermal baths in the town of Spa, Belgium, fed by natural mineral water, with saunas, hammams and separate textile and naturist relaxation areas.

Noboribetsu, Hokkaido

A plain neighborhood bathhouse in Noboribetsu, Hokkaido, offering 100% source-fed hot spring water in two mineral varieties, about 10 minutes from the station.

Budapest

A large thermal bath complex in Budapest's City Park with indoor and outdoor pools, saunas, and day passes for walk-in visitors.

Berlin

A saltwater thermal pool under a concrete dome near Berlin's Tempelhofer Feld, with sauna, steam room and occasional DJ nights.