Spas with fitness center

Killarney, Munster

Hotel spa and leisure studio at The Killarney Park with a 20m pool, outdoor jacuzzi, sauna and steam room, open to hotel guests only.

Chicago, Illinois

A hotel spa on Trump Chicago's mezzanine level offering day passes, 22 treatments, a heated pool, steam room, sauna and fitness club; minimum age 16.

Hua Hin, Prachuap Khiri Khan

Hotel spa at The Standard, Hua Hin, offering 11 treatments, ice bath therapy, and a day pass option at a beachfront resort on Naresdamri Road.

Philadelphia, Pennsylvania

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

Brussels

Hotel spa on the 25th floor of The Hotel Brussels, with city views, sauna, steam room, salt sauna and a Technogym fitness floor.

Boston, Massachusetts

Hotel spa inside the Four Seasons One Dalton in Back Bay, with six treatments, a couples' suite and a 64-foot lap pool, open to hotel guests.

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.

Rogaška Slatina, Savinjska

Wellness center at Grand Hotel Rogaška in Rogaška Slatina, Slovenia, with pools, saunas and fitness; day pass available by reservation.

Miami, Florida

A 20th-floor hotel spa in Downtown Miami's JW Marriott Marquis offering massages, facials, body treatments and separate men's and women's lounges.

Miami, Florida

Hotel spa inside the InterContinental Miami, open daily with a day pass option, 11 treatments and a signature Raindrop Massage.

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.

Hunter Valley, New South Wales

A resort spa inside Avani Cypress Lakes in Pokolbin, open to hotel guests for treatments, thermal pools, outdoor baths and a fitness and yoga space.

Naples, Florida

A boutique hotel in downtown Naples with a heated outdoor pool, whirlpool spa and cabanas, open only to overnight guests.

Boston, Massachusetts

Hotel spa inside the Omni Boston Hotel at the Seaport, with eight treatment rooms and a rooftop pool, open to hotel guests only.

Stockholm, Stockholm County

Hotel spa at Stockholm's Grand Hôtel, right on the water opposite the Royal Palace, with sauna, pool and cold plunge for guests only.

Washington, D.C., District of Columbia

Hotel spa at Pendry Washington DC - The Wharf with eucalyptus steam rooms, a heated whirlpool and an outdoor terrace pool, open daily 10am-6pm.

Four Corners, Florida

Hotel spa at Omni Orlando Resort ChampionsGate offering massages, facials and nail services, open to day-pass guests as well as hotel guests.

Scottsdale, Arizona

A hotel spa at Four Seasons Scottsdale at Troon North offering massages, facials, a full salon and 24-hour fitness access, guests only.

Băile Herculane, Caraș-Severin

A 4-star hotel in central Băile Herculane with thermal pools, saunas, balneo and physiotherapy treatments, open to overnight guests.

Tucson, Arizona

Lakeside Spa at this 398-room desert resort in Tucson is open to hotel guests only, with two heated pools, a Jacuzzi and mountain views of Catalina range.

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.

San Diego, California

A rooftop hotel spa in San Diego's Gaslamp Quarter offering treatments and a 24/7 fitness center, open to hotel guests and day-pass visitors.

Atlanta, Georgia

Hotel spa inside The St. Regis Atlanta in Buckhead, with pool, jacuzzi and whirlpool, open daily 9am-7pm for hotel guests.

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.