Spas with moderate

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.

North Royalton, Ohio

A North Royalton day spa built around a salt room and sauna, with adults-only halotherapy sessions on a walk-in or reserved basis.

Copenhagen, Capital Region

A Nørrebro day spa built around a salt room and sauna, open daily for walk-in visits, adults only.

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.

Koh Samui, Surat Thani

A day spa in Bo Phut, Koh Samui, open daily 9am to 11pm with a sauna and traditional Thai treatments for solo visitors and couples.

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.

Minneapolis, Minnesota

A Northeast Minneapolis wellness studio rooted in Traditional Chinese Medicine, offering sauna access by reservation in the Bottineau neighborhood.

Ojai, California

A small, independently owned day spa in Ojai offering facials, massage, head spa treatments, infrared sauna and salt therapy.

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.

Park City, Utah

A sauna-and-cold-plunge day spa in Park City with memberships, private group buyouts, and reservation-only access.

Nashville, Tennessee

A Gulch studio for infrared sauna and cold plunge sessions in private suites, open daily with reservations required.

Pamukkale, Denizli

A 315-room thermal resort in Karahayıt near Pamukkale with its own thermal pools, pine-shaded gardens and on-site dining, open to hotel guests only.

Vienna

A day-pass bathhouse on Handelskai in Leopoldstadt with a sauna and thermal pool, open daily 10am–10pm.

Nashville, Tennessee

A hotel wellness area at Sheraton Music City near Nashville airport, open to guests 21 and up, with sauna, steam room, pools and a whirlpool.

Reykjavik, Capital Region

An oceanfront thermal bath in Kópavogur near Reykjavik, open daily with outdoor pools facing the sea and walk-in day passes.

Houston, Texas

A moderate-priced day spa on the 23rd floor of a downtown Houston office tower, open Wednesday through Sunday with a relaxation lounge and sauna.

Carmel-by-the-Sea, California

A hotel spa inside Carmel-by-the-Sea's Hyatt Regency Monterey property, with hydrotherapy, sauna and a relaxation lounge for guests and couples.

Jerusalem, Jerusalem District

A hotel spa in Jerusalem with sauna, hot tub and thermal pool, open to walk-ins and day-pass guests most days of the week.

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.