Spas with moderate

Bormio, Lombardy

Family-friendly thermal baths in Bormio with chlorine-free pools heated to 37–40°C, plus sauna, steam room and adult-only wellness areas.

Durango, Colorado

A hot springs resort in the Animas Valley near Durango, Colorado, with 32 mineral pools, cold plunges, a lap pool and private cedar soaking tubs.

Vail, Colorado

Adults-only day spa at The Charter at Beaver Creek with saltwater pools, steam room, sauna and a day pass for treatments or facility access.

Palm Springs, California

Hotel spa inside the Avalon in Palm Springs, open Thursday through Monday, with a $75 day pass covering jacuzzi, sauna, cold plunge and steam rooms.

Temescal Valley, California

Adults-only hot springs resort in Temescal Valley with 19 outdoor mineral pools, red clay baths, and a cave-like grotto, open daily 9:30am-5pm.

Krynica-Zdrój, Lesser Poland

Mountain resort spa in Krynica-Zdrój with indoor and outdoor pools, a sauna complex, and a clothing-optional 18+ zone; day passes available.

Miami, Florida

A co-ed Turkish hammam and day spa in North Miami offering a $125 day pass with saunas, steam rooms, a hydromassage pool and an on-site Turkish restaurant.

San Diego, California

A walk-in day spa in San Diego's Hillcrest neighborhood with massage, cryotherapy, salt therapy and a $100 all-day wellness pass.

Chantilly, Virginia

King SPA is a Korean bathhouse in Chantilly, VA, with gender-separated clothing-optional baths, mixed saunas, a restaurant, and day passes for walk-ins.

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

Seattle, Washington

Korean day spa in Lynnwood with hydrotherapy pools, FIR rooms and a Korean restaurant, open for walk-ins on a day-pass basis.

Sierraville, California

A non-profit hot springs retreat near Lake Tahoe with natural spring pools, reservation-only day and evening soaks, camping and rooms, closed Mondays and

Bad Wörishofen, Bavaria

Adults-only thermal baths in Bad Wörishofen with palm-house pools, mineral pools and saunas; day passes available, minimum age 16.

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.

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.

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.

Vail, Colorado

A day spa and recovery club in downtown Vail with hot tub, sauna, steam room, cold plunge and salt lounge, plus day passes and fitness access.

Aspen, Colorado

Adults-only hotel spa at Viewline Resort Snowmass with a $25 day pass, steam rooms, outdoor pool and whirlpool, reservations required.

Palm Springs, California

A 16-room adults-only hotel in Desert Hot Springs with three natural mineral-water pools fed by a 350-foot geothermal well, plus a small on-site spa and

Rogaška Slatina, Savinjska

Wellness center at Grand Hotel Rogaška in Rogaška Slatina, Slovenia, with pools, saunas and fitness; day pass available by reservation.

Hanoi

Day spa in Hanoi's Old Quarter with a herbal steam room, Himalayan salt stone room and jacuzzi, open daily 10am–10pm.

Santa Fe, New Mexico

A 16,000-square-foot adults-only hotel spa at Hilton Buffalo Thunder near Santa Fe, with separate men's and women's saunas, steam rooms and whirlpools.