Spas with hotel guests only

Riviera Maya, Quintana Roo

Adults-only spa inside the all-inclusive Ocean Riviera Paradise resort in Playa del Carmen, with sauna, Turkish bath and four treatment options via day pass.

Santa Fe, New Mexico

A 77-acre hot springs resort outside Santa Fe with spring-fed thermal pools, day-pass soaking packages from $175, and overnight lodging.

Scottsdale, Arizona

Andalusian-style resort spa at the base of Camelback Mountain with saunas, steam rooms, a hammam and three pools, open to guests 21 and up.

Scottsdale, Arizona

Adults-only resort spa at the Andaz Scottsdale with treatment suites, a private pool, fitness center and cabana bookings, day pass available.

Boston, Massachusetts

Hotel spa inside Raffles Boston pairing Guerlain facials and massages with a 65-foot lap pool, hot tub, sauna, steam room and three private treatment suites.

Scottsdale, Arizona

A hotel spa at JW Marriott Desert Ridge with sauna, steam rooms, a sanctuary pool, bistro and salon, open to day-pass guests as well as hotel guests.

Vail, Colorado

Hotel spa at The Arrabelle in Lionshead Village, Vail, with 11 treatment rooms, a fitness center and locker-room steam rooms, open to hotel guests.

Park City, Utah

Hotel spa in Canyons Village at the Grand Summit with sauna, steam room, three whirlpools and a 22-treatment menu including ski-recovery massages.

Jackson Hole, Wyoming

A hotel spa at Rustic Inn Creekside Resort in Jackson Hole with dry sauna, eucalyptus steam room, outdoor pool and hot tub, open to overnight guests only.

Palm Springs, California

Sante Spa is the adults-only resort spa at the Riviera Palm Springs, with 18 treatment rooms, a Watsu pool, steam room and validated valet parking.

Las Vegas, Nevada

Adults-only hotel spa inside Westgate Las Vegas offering massages, facials, salon services, sauna, steam room and a thermal pool, open daily 9am-6pm.

Palm Beach, Florida

A hotel spa at the Palm Beach Marriott Singer Island resort offering massages, facials and body treatments, open daily 9am–6pm, guests 16+ only.

Vail, Colorado

Hotel spa inside the Sonnenalp Resort in Vail with indoor-outdoor pools, whirlpools, an oxygen bar and $50 day passes when space allows.

Vail, Colorado

Hotel spa at the Westin Riverfront in Avon near Vail, with 14 treatment rooms, a saline lap pool, three infinity hot tubs and day passes for non-guests.

Las Vegas, Nevada

Spa Aquae is JW Marriott Las Vegas Resort & Spa's day spa in Summerlin, with 18 treatments, couples massages and a steam room, open daily 8am-7pm.

Park City, Utah

A 27-room resort spa at Montage Deer Valley in Park City, open to hotel guests with a pool, steam room, sauna and cold plunge.

Boca Raton, Florida

Hotel spa at The Boca Raton with 44 treatment rooms, a spa pool and waterfall whirlpools, open to resort guests, club members and day-pass visitors by

Calistoga, California

Spa Talisa is the adults-only spa at the Four Seasons Resort Napa Valley in Calistoga, with vineyard-view gardens, barrel saunas and a sunken whirlpool for

San Diego, California

Hotel spa at Coronado Island Marriott Resort with massages, facials, body scrubs, a steam room and couples treatments, open daily 10 am to 4 pm.

Tucson, Arizona

Adults-only hotel spa at El Conquistador Tucson with a salt therapy lounge, heated outdoor pool and mountain views, day passes available to hotel guests.

Mendocino, California

A redwood hot tub and sauna spa in Mendocino village, offering massage and private soaks mainly for guests of the adjoining Sweetwater Inn.

Tuscany

A five-star resort in the Tuscan countryside built around a natural thermal spring, with day passes from €39 for outdoor thermal pools, hydromassage circuits

Miami, Florida

A 12,000-square-foot hotel spa at Coral Gables' Biltmore, with eucalyptus steam rooms, Himalayan salt saunas and a couples suite; adults-only, reservation

Scottsdale, Arizona

Hotel spa at The Phoenician in Scottsdale, open to guests 18+ who book a massage, facial, or body treatment, with sauna, steam room and a rooftop pool.