Spas with upscale

Tucson, Arizona

Six-room hotel spa at Hacienda del Sol in Tucson, open daily 9-6, taking both resort guests and local walk-ins for massages, facials and body treatments.

Napa Valley, California

Adults-only hotel spa in downtown Napa with thermal circuits, sauna, steam and cold plunge, plus massages, facials and medical aesthetics.

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.

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+.

Detroit, Michigan

A downtown Detroit day spa with a thermal pool, sauna and steam room, offering about 70 treatments including a $240 couples massage.

Orlando, Florida

Adults-only hotel spa at the Hilton Orlando with a sauna, steam room, cold plunge and thermal pools, plus couples treatments and HydraFacials.

Scottsdale, Arizona

Adults-only hotel spa at W Scottsdale with thermal circuits, sauna, steam, cold plunge and a robotic Aescape massage option.

Bridgetown, Christ Church

Hotel spa at Accra Beach Hotel in Christ Church, Barbados, with six treatment rooms, a sauna and steam room, open daily 8am-7pm for hotel guests.

San Diego, California

A La Jolla medical spa specializing in lymphatic drainage, colon hydrotherapy and detox treatments, open since 1993, adults only, by reservation.

Calistoga, California

A 1952 Calistoga hot springs resort with three mineral pools at 85, 95 and 104°F, mud baths, overnight rooms and a day-pass option.

Scottsdale, Arizona

Hotel spa at the mid-century Hotel Valley Ho in South Scottsdale, with sauna, steam room and two pools, open to hotel guests only.

Palm Springs, California

Downtown Palm Springs day spa built around a natural hot mineral spring, with private mineral baths, sauna, steam room and massage.

Sonoma, California

Hotel spa at The Lodge at Sonoma with an outdoor terrace, soaking pool, plunge pool and barrel sauna, open daily 9am-5pm, adults-only, reservation required.

Sedona, Arizona

A resort spa at Amara in Sedona with outdoor baths, an infinity pool and a relaxation lounge, open only to hotel guests.

Milwaukee, Wisconsin

East Town Spa in Milwaukee's Juneau Town combines a full-service salon and med spa with a thermal circuit of sauna, steam, pools and cold plunge.

Dallas, Texas

A hotel spa at Omni Las Colinas in Irving, Texas, with an outdoor pool and bath area, open to hotel guests along Lake Carolyn.

San Diego, California

A resort spa on a 44-acre Mission Bay island in San Diego, open to hotel guests, with sauna, steam room and pool access.

Scottsdale, Arizona

Adults-only resort spa in Fountain Hills with sauna, steam room and outdoor pools, offering day passes and an amethyst facial as its signature treatment.

Miami, Florida

Hotel spa at Gale Miami with a hammam, sauna and outdoor pool on the 9th floor, open to hotel guests only.

Cancún, Quintana Roo

A boutique hotel near Cancún airport with a small wellness wing — pool, jacuzzi, sauna, steam room and temazcal — open to day-pass visitors.

San Antonio, Texas

Full-service resort spa at the Hyatt Regency Hill Country in San Antonio, with thermal circuits, cold plunge and day passes open to non-guests.

Miami, Florida

mySpa at InterContinental Miami is a hotel spa in Downtown Miami offering a sauna, steam room, pools and a cold plunge, open to hotel guests only.

San Diego, California

A hotel wellness facility at InterContinental San Diego with an outdoor pool, sauna, steam room and fitness center, open to hotel guests only, ages 18+.

Jekyll Island, Georgia

Hotel spa at Jekyll Island Club Resort offers outdoor baths and a pool with ocean views, open only to resort guests.