Spas with walk-ins welcome

Lake Como, Lombardy

A day spa inside the Castello di Casiglio parkland near Erba, offering a 3-hour pass with heated indoor-outdoor pools, saunas and a Turkish bath; adults and

Saint-Malo, Brittany

A seafront thalassotherapy center in Saint-Malo with an Aquatonic seawater pool circuit, day passes, and multi-day cure packages in a Belle-Époque building.

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.

Monroe, Utah

Natural hot spring pools fed by mineral water in rural Monroe, Utah, open 24/7 with day-pass soaking and funky bus and cabin lodging on site.

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

Nashville, Tennessee

Day spa in Nashville's Maxwell neighborhood built around olive-oil massages, a DIY Mud Lounge, salt room and infrared sauna.

Los Angeles, California

Women-only Korean day spa in Koreatown, LA with saltwater, mineral and cold pools, a salt room, and walk-in day passes.

Edinburgh, Scotland

One Spa is an adults-only day spa in Edinburgh's city centre with a rooftop Hydropool, thermal suite and day-pass access.

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.

Pagosa Springs, Colorado

Victorian-style bathhouse in downtown Pagosa Springs with mineral soaking tubs, a rooftop tub, sauna, cold plunge and on-site massage.

Gothenburg, Västra Götaland County

A rooftop pool club and spa spanning two floors of the Jacy'z hotel in Gothenburg, with heated pools, sauna, steam room and a bar-restaurant, open for day

Saturnia, Tuscany

Walk-in thermal park in the Maremma countryside with four outdoor sulfur pools, hydromassage jets and a vascular circuit fed by a 3,000-year-old spring.

Mornington Peninsula, Victoria

Geothermal hot springs and day spa in Fingal on the Mornington Peninsula, with a family-friendly Bath House and an adults-only Spa Dreaming Centre.

Houston, Texas

A Central Business District day spa with a rooftop pool, offering facials, massages and body treatments, open daily with walk-in access.

Los Angeles, California

Women-only Korean spa and sauna in Koreatown with a $25 day pass, body-scrub massages and clothing-optional bathing areas.

Cincinnati, Ohio

Day spa in Columbia-Tusculum, Cincinnati, with massage, facials, an infrared/Himalayan salt sauna and a $99 signature sampler package.

Philadelphia, Pennsylvania

A Center City West day spa and salon on the Avenue of the Arts with two therapy suites that pair infrared heat or red light with salt air.

Atlanta, Georgia

A 24-hour Korean bathhouse and spa in Doraville near Atlanta, with heat rooms, a restaurant, and day-pass access for walk-ins.

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

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.

Kusatsu, Gunma

A large open-air hot spring bath in Nishinokawara Park, Kusatsu, set among forest with mountain and seasonal views, open daily for walk-ins.

Indianapolis, Indiana

A moderate-priced day spa in northwest Indianapolis offering float therapy, salt room sessions, infrared sauna, cold plunge and foot detox, closed Mondays.

Charleston, South Carolina

Day spa and yoga studio on King Street in Charleston offering massage, facials, body treatments, a salt cave and infrared saunas.