Spas with moderate

Milan, Lombardy

Adults-only day spa in a Liberty-style building near Milan's Parco Sempione, with thermal pools, saunas, steam room and a hydrotherapy circuit.

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.

Orlando, Florida

A 10,000-square-foot hotel spa at Westgate Lakes Resort in Orlando with massages, facials, sauna, steam room and a fitness studio, open daily.

Charlotte, North Carolina

A moderate-priced day spa in Charlotte's SouthPark area with a sauna, steam room and thermal pool alongside massage, facial and body-treatment menus.

Băile Felix, Bihor

Strand Apollo-Felix is a year-round thermal pool complex in Băile Felix, Romania, with indoor and outdoor pools open daily from 8am to 8pm.

Evian-les-Bains, Auvergne-Rhône-Alpes

A Hilton hotel spa on Lake Geneva's shore in Évian-les-Bains, open to day-pass visitors by reservation.

Hot Springs, Arkansas

A day spa on Central Avenue in Hot Springs with outdoor mineral soaking tubs, cold plunge, infrared sauna, massage and an on-site café.

Asan, South Chungcheong

Hot springs resort spa in Asan with thermal pools, sauna and a relaxation lounge, open daily on a walk-in day-pass basis.

Beitou, Taipei

Hotel spa in Beitou with a thermal pool, open to day-pass visitors as well as hotel guests.

Redstone Historic District, Colorado

A ranch property in Colorado's Crystal River Valley with three tiered natural hot springs pools open to day visitors and overnight guests alike.

Santa Fe, New Mexico

A Santa Fe day spa combining yoga, pilates and nia classes with spa treatments, a café and a boutique, open daily 9am–7pm.

Bad Kissingen, Bavaria

A Bavarian state-run thermal bath in Bad Kissingen offering day passes with walk-in access, open most days including evenings.

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.

Byron Bay, New South Wales

Hotel day spa at Crystalbrook Byron offering customizable massages and facials, open daily with Sunday by appointment only.

Calistoga, California

A clothing-optional hot springs retreat outside Calistoga with eight mineral pools, spa bodywork, and day-pass, camping, and lodging options.

Los Baños, Laguna

A natural spring resort near Mount Makiling in Calauan, Laguna, with outdoor pools, forest trails, and day passes offered every day of the week.

Miami, Florida

A hotel spa in downtown Miami with a day pass covering sauna, steam, cold plunge and thermal pools, plus 13 treatments on the menu.

San Francisco, California

A Japantown bathhouse open for 50+ years, with a Japanese-style thermal pool and relaxation lounge, reservation required, adults only.

Palm Springs, California

A 10-room mineral hot springs hotel in Desert Hot Springs near Palm Springs, offering day passes to its 120°F spring-fed pools, sauna and massage rooms.

Karjalohja, Uusimaa

Lakeside resort spa on Lohjanjärvi in Karjalohja, about an hour from Helsinki, with a day pass, thermal pool, salt room and restaurant.

San Miguel de Allende, Guanajuato

A Saturday-only hot springs day spa near San Miguel de Allende with outdoor thermal pools and walk-in access.

Palm Springs, California

Resort spa in Desert Hot Springs with mineral thermal pools, open to day-pass visitors and hotel guests, geared toward couples and families.

San Francisco, California

An adults-only bathhouse in San Francisco's Tenderloin with a thermal pool and an on-site restaurant, open daily except Tuesdays.

Naples, Florida

A hotel spa inside the Inn on Fifth in downtown Naples, open daily for massages, facials, nail services, sauna, steam room and lounge access.