Spas with adults only

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.

Tbilisi

A medical spa in Old Tbilisi built around natural sulfur-mineral water and volcanic mud, operating since 1938, open daily 10am–9pm.

Hot Springs, Arkansas

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

London, England

A Russian-style banya bathhouse in Belgravia offering oak-lined steam rooms, cold plunge pools and leaf-massage rituals, with day passes by reservation only.

Queenstown, Otago

Adults-only bathhouse in central Queenstown with heated, ambient and cold pools, sauna and steam room, day pass $99.

Boston, Massachusetts

A Norwood, Massachusetts day spa built around a hot-cold hydrotherapy circuit of mineral baths, saunas, steam and cold plunges, open daily with a day pass.

Jackson Hole, Wyoming

Hotel spa inside the Rusty Parrot Lodge in downtown Jackson Hole offering massage, facials and couples treatments with hot tub access, day passes welcome.

Skippack, Pennsylvania

A moderate-priced day spa in Skippack, Pennsylvania, offering about 10 treatments with walk-in appointments and on-site parking.

Portland, Oregon

An 18-and-up, clothing-optional spa in Portland's Kerns neighborhood with a salt hot tub, sauna, steam room and cold plunge, reservation required.

Orlando, Florida

Adults-only hotel spa at Disney's Grand Floridian Resort with massage, salon services and a fitness center, open to walk-ins daily 9am-6pm.

Seattle, Washington

A quiet, clothing-optional day spa in Greenwood with soaking pools, saunas and a steam room, women-owned and open to all genders on Wednesdays.

Miami, Florida

A walk-in sauna and cold plunge studio in Miami built around contrast therapy, with day passes and split morning and evening hours.

Denver, Colorado

A 6,000-square-foot hotel spa in downtown Denver's Granite Tower, open to day-pass visitors 18 and older for $40 to $75.

Marana, Arizona

Adults-only hotel spa at Dove Mountain Resort in Marana with desert-themed treatments, an infinity-edge pool, sauna and steam room; facility access comes with

Lake Tahoe, California

A 17-room, adults-only hotel spa at Lake Tahoe's Ritz-Carlton with a heated lap pool, sauna and steam room; day pass access requires booking a treatment.

Portland, Oregon

Adults-only hotel spa in downtown Portland with a $50 day pass, infinity pool, sauna, steam room and cold plunge shower, booked in advance only.

Charleston, South Carolina

A King Street medical spa in Charleston's Harleston Village offering injectables, laser and skin treatments through nurse-practitioner-led membership plans.

Santa Ynez, California

Adults-only resort spa inside Chumash Casino Resort in Santa Ynez with 21 treatments, a mineral pool, cold plunge and couple's suites.

Napa Valley, California

Adults-only hotel spa in Napa Valley with a co-ed thermal circuit of sauna, steam room and cold shower, open daily 10am–6pm; day passes available.

Hunter Valley, New South Wales

Large day spa at Chateau Elan in Hunter Valley with 17 treatment rooms, a float tank, outdoor mineral spas and couples' treatments; day passes and walk-ins

Boston, Massachusetts

Adults-only hotel spa at Encore Boston Harbor in Everett with separate men's and women's heat and water facilities, booked by appointment.

Las Vegas, Nevada

An adults-only hotel spa inside Encore Las Vegas with whirlpool, sauna and steam room, open daily for treatments and day passes, walk-ins welcome.

San Diego, California

Adults-only hotel spa in Carmel Valley with a hydrotherapy circuit, two fireplace lounges, and a $100 day pass covering pools and fitness facilities.

Washington, D.C., District of Columbia

Hotel spa at Four Seasons Washington, DC with a private contrast therapy room, pool, and an adults-only, couples-friendly treatment menu.