Spas with relaxation lounge

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.

Naples, Florida

Hotel spa at The Ritz-Carlton, Naples with 23 treatments, steam rooms, plunge pool and separate men's and women's lounges, open daily 9am–6pm.

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.

Los Angeles, California

Four Seasons hotel spa in Beverly Hills with a steam room, rooftop pool, fitness center and eight treatments, open daily, day passes available.

Scottsdale, Arizona

Resort spa at Camelback Inn in Scottsdale with 20 treatment rooms, a thermal circuit and day-pass access open to non-guests.

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.

Palm Springs, California

A 38,000-square-foot resort spa at JW Marriott Desert Springs in Palm Desert offers day passes, saunas, a saltwater lap pool and couples suites.

Denver, Colorado

A hotel spa in downtown Denver with a $150 day pass covering pool, steam room, whirlpool and fitness centre access, open to non-guests.

Houston, Texas

A Four Seasons hotel spa in downtown Houston with three treatment rooms, a couples' suite and rooftop pool access, open to day-pass guests.

Philadelphia, Pennsylvania

A 57th-floor hotel spa in Center City Philadelphia with an infinity-edge pool, 11 treatments, and a day pass that pairs pool access with a service.

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.

Jackson Hole, Wyoming

A hotel spa at Four Seasons Jackson Hole with treatment suites, whirlpools, a cold tub, salon services and fitness facilities, reservation-only.

Vail, Colorado

A hotel spa at Grand Hyatt Vail with three treatments, an outdoor heated infinity pool, hot tubs and cold plunges along Gore Creek.

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.

New York City, New York

A penthouse-level spa at Hotel Chelsea in Manhattan with a rooftop terrace, sauna, steam rooms and a 16-treatment menu for guests 18 and over.

San Diego, California

Adults-only day and hotel spa in Rancho Bernardo with gardens, whirlpools, a steam room and an 18-treatment menu, open daily 9am-6pm.

Park City, Utah

A hotel spa at Stein Eriksen Lodge in Park City with indoor/outdoor pools, saunas and cold plunge, open to lodge guests for about eight treatments.

Asheville, North Carolina

Adults-only hotel spa in Asheville with a fiber-optic-starred lap pool, waterfall pools, saunas and an electronics-free policy; day passes are limited and

Miami, Florida

Hotel spa at The Ritz-Carlton Key Biscayne, Miami, with treatment suites, sauna, steam room and whirlpool, open to hotel guests 18 and up by appointment.

Aspen, Colorado

Hotel spa at Viceroy Snowmass in Aspen with 20 treatments, a plunge pool and couples massage rooms, open daily 10am-6pm by reservation.

Miami, Florida

Adults-only hotel spa on Belle Isle near South Beach with a hammam, sauna, ice room, infinity pool and a day pass option for non-guests.

Catskills, New York

Adults-only hotel spa in Saugerties with a day pass, pool deck, sauna, hot tub and cold plunge overlooking the Esopus Creek.

Jackson Hole, Wyoming

A small, guests-only spa tucked inside the White Buffalo Club, a luxury boutique hotel three blocks from Jackson's Town Square.

Miami, Florida

Hotel spa at The Setai in Miami Beach with 7 ocean-view treatment rooms, 5 couples suites, saunas, steam and a cold plunge.