Spas with reservation required

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.

Galway, Connacht

Adults-only hotel spa in Galway with a thermal suite, hydro pool and sauna; day pass runs about €50 and reservations are required.

Calistoga, California

A 20-treatment hotel day spa in Santa Rosa with an indoor caldarium plunge pool, eucalyptus steam rooms, and walk-in or reserved day passes for adults 18+.

Santa Fe, New Mexico

Small hotel day spa in downtown Santa Fe with a soaking pool, five treatment rooms and 25 services, open daily 8am-5pm by reservation.

Idaho City, Idaho

A reservation-only hot springs soak in Idaho City with private tubs, a steam room and a $30 day pass, open five days a week.

Miami, Florida

Hotel spa inside Trump National Doral with 42 treatments, couples massages, sauna, steam room, cold plunge and jacuzzi, open daily 9am-7pm.

Philadelphia, Pennsylvania

Hotel spa in Center City Philadelphia with a heated indoor saltwater pool, fitness center and day-pass access for non-guests.

Aspen, Colorado

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

Sedona, Arizona

Adults-only resort spa in Sedona with outdoor hot tubs, steam rooms and a 30-treatment menu, open daily with walk-ins and day passes.

Portland, Oregon

A 21-and-up day spa in Portland's Irvington neighborhood built around vinotherapy, with wine-infused baths, massages and Caudalie facials.

Scottsdale, Arizona

Hotel spa inside Hotel Solaya in South Scottsdale built around Tod Miller's proprietary BodyWalking compression technique, with four treatments and a $335

Chicago, Illinois

A moderately priced day spa in Chicago's Lakeview neighborhood focused on Chinese-style head and scalp treatments, open to adults 16 and up.

Pittsburgh, Pennsylvania

A South Hills float center offering sensory-deprivation float tanks alongside sauna and cold plunge, with a 60-minute float starting at $89.

Washington, D.C., District of Columbia

A float therapy studio in Alexandria offering sensory-deprivation floats, sauna, cold plunge, and red light therapy sessions.

Cary, North Carolina

A Cary float center offering sensory-deprivation tank sessions and an oxygen bar, with a 60-minute float running $89.

Cedar Park, Texas

Cedar Park float spa offering sensory-deprivation float therapy plus sauna, steam room and cold plunge, open daily 8am-10pm.

San Diego, California

Hillcrest float spa offering sensory-deprivation float sessions and an oxygen bar, with walk-ins welcome but reservations required.

Austin, Texas

Float tank spa in South Austin's South Lamar area offering sensory-deprivation floats, sauna and cold plunge, with walk-ins welcome.

Utica, Michigan

Single-facility float spa in Utica offering 60-minute sensory-deprivation float pod sessions, walk-ins welcome but reservations recommended.

Indian Land, South Carolina

Float therapy center in Indian Land, SC (serving Charlotte and Fort Mill), offering 60-minute sensory deprivation floats plus an oxygen bar.

Raleigh, North Carolina

Single-purpose float spa in North Raleigh offering 60-minute sensory-deprivation pod sessions, open daily with walk-ins accepted.

Washington, D.C., District of Columbia

Day spa in Lanier Heights, DC, offering massage, facials and skincare products, with walk-ins welcome and online booking.

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