Spas with thermal pool

Miami, Florida

Hotel spa inside Dua Miami, Autograph Collection in Brickell, open daily 9am-6pm, with sauna, steam room, cold plunge and couples massage rooms.

Orlando, Florida

Family resort near Walt Disney World with a pirate-themed pool complex and a spa offering day passes and couples treatments.

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.

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 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.

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

San Diego, California

Hotel spa at the historic Hotel del Coronado with an ocean-view pool, 20 treatments, and a seaweed-based signature Ocean Essence Ritual.

Naples, Florida

Hotel spa at The Ritz-Carlton, Naples with 23 treatments, steam rooms, plunge pool and separate men's and women's lounges, open daily 9am–6pm.

Vail, Colorado

A hotel spa at Grand Hyatt Vail with three treatments, an outdoor heated infinity pool, hot tubs and cold plunges along Gore Creek.

Philadelphia, Pennsylvania

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

Whistler, British Columbia

Hotel spa at the Westin in Whistler Village with 19 treatments, couples massage, and free access to the hotel's pools, sauna, steam room and gym.

Osprey, Florida

Hotel spa and pool deck at a moderate-price resort in Osprey, Florida, with sauna, steam room and thermal circuits for overnight guests.

Fort Lauderdale, Florida

Hotel spa at The Atlantic Resort on Fort Lauderdale Beach with sauna, steam room, cold plunge and thermal pool, for overnight guests only.

Beitou, Taipei

Hotel spa in Beitou with a thermal pool, open to day-pass visitors as well as hotel guests.

San Diego, California

A hotel spa at the Handlery Hotel in Mission Valley, San Diego, with sauna, steam room, cold plunge and thermal pools for guests.

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.

Sedona, Arizona

Hotel spa near Bell Rock in Sedona with sauna, steam room, cold plunge and pools, open to resort guests only.

Boston, Massachusetts

A hotel spa inside Mandarin Oriental, Boston's Back Bay property, open to hotel guests only, with sauna, steam room, pools and a cold plunge.

Arima Onsen, Hyogo

Hotel spa in Arima Onsen with Arima's rare iron-rich "ginsen" waters, outdoor baths, sauna and jacuzzi, run as an all-inclusive overnight stay.

San Diego, California

Hotel spa at Carté Hotel San Diego Downtown with a heated saltwater pool, whirlpool, 28,000 sq ft fitness club with sauna and steam room, open to guests only.

Philadelphia, Pennsylvania

A hotel spa inside the Four Seasons Comcast Center tower in Center City Philadelphia, open to overnight guests with an infinity pool and skyline views.

Big Island, Hawaii

A hotel spa at Hilton Waikoloa Village on Hawaii's Big Island, with a pool and thermal pool, open to hotel guests.

Scottsdale, Arizona

A resort spa at JW Marriott Phoenix Desert Ridge with a thermal pool, relaxation lounge and on-site café, open to hotel guests and day-pass visitors.