Spas with fitness center

Tenerife, Canary Islands

A hotel spa at Bahía del Duque in Costa Adeje with an outdoor seawater thalassotherapy circuit, hammam, saunas and a cold plunge, open to day visitors.

Hammamet, Nabeul

Seafront thalasso spa in Hammamet Est with a thermal pool, 42 treatments, and day passes open daily from 8am to 7pm.

Miami, Florida

A beachfront resort spa in North Beach, Miami with cryotherapy, a floating salt bath, sauna, steam and a cold plunge, open to walk-ins and day-pass guests.

Tuscany

Hotel spa inside Florence's Four Seasons, with a walled garden pool, whirlpool, sauna, steam room and couples suite, open to day-pass guests.

The Hamptons, New York

Oceanfront resort spa in Montauk with a seawater and marine-based treatment menu, hydrotherapy, contrast bathing, and a heated saltwater pool.

Tucson, Arizona

A resort spa in Tucson's Starr Pass area with a saline lap pool, sauna and fitness center, plus signature treatments from $159 for hotel guests.

Portorož, Coastal-Karst

Hotel spa on Portorož's seafront promenade with heated seawater and thermomineral pools, open to day visitors as well as hotel guests.

Reykjavik, Capital Region

Eight oceanfront geothermal pools in Hvalfjörður, 45 minutes from Reykjavík, plus steam baths, a bistro and guest houses for rent.

Ein Bokek, Southern District

Hotel spa on the Dead Sea shore in Ein Bokek with a heated mineral-water pool, sulphur pools, hammam and sauna; day passes open to adults 16 and up.

Tucson, Arizona

Hotel spa at Omni Tucson National Resort with 12 treatment rooms, a couples suite, salon services, and day passes open to both guests and locals.

Scottsdale, Arizona

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

Park City, Utah

Hotel spa at Pendry Park City with six treatment rooms, a rooftop pool, whirlpool and herbal steam room, open daily 8:30am–4:30pm.

Austin, Texas

Hotel spa at Hotel Viata in West Lake Hills with treatment rooms, a couples suite, pool, sauna, steam room and a day-pass option for amenity access.

Miami, Florida

AVEDA hotel spa at The Palms in Mid-Beach Miami, offering Ayurvedic-inspired massages, facials and salon services with pool and beach access included.

Santa Barbara, California

A 42,000-square-foot hotel spa in Santa Barbara with an adults-only pool, redwood sauna, eucalyptus steam room, cold plunge and rooftop terrace.

Los Angeles, California

Downtown LA hotel spa at the Ritz-Carlton with massages, facials, a couples suite, rooftop pool and gym; outside guests need to book a treatment to enter.

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.

Las Vegas, Nevada

An adults-only hotel spa inside Encore Las Vegas with whirlpool, sauna and steam room, open daily for treatments and day passes, walk-ins welcome.

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.

Milan, Lombardy

A luxury hotel spa inside Four Seasons Hotel Milano with a 14-metre pool under a vaulted ceiling, sauna, gym and private suites for couples' treatments.

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.

Nashville, Tennessee

A hotel spa in downtown Nashville with six treatment rooms, a rooftop infinity pool, and day passes open to non-guests.

Palm Beach, Florida

A Forbes Five-Star resort spa in Palm Beach offering 22 treatments, a eucalyptus steam room, saltwater whirlpool, and day-pass access.