Spas with upscale

Calistoga, California

A 20,000-square-foot resort spa in Calistoga with five geothermal pools, Calistoga mud treatments, and a day pass for non-hotel guests.

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.

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.

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.

Tucson, Arizona

A hotel spa inside the 1929 Hacienda del Sol Guest Ranch Resort in Tucson, offering facials, massages and body treatments to resort guests only.

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.

San Francisco, California

Adults-only hotel spa in Sausalito, California, offering day passes alongside yoga and a restaurant on site.

South Haven, Michigan

An adults-only glamping resort and pool club at South Haven Country Club with a day-pass spa area featuring a pool, sauna and relaxation lounge.

Encinitas, California

Adults-only day spa in Leucadia, Encinitas, about a mile from the beach, with private suites, a relaxation lounge and movement classes.

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.

Riviera Maya, Quintana Roo

A resort spa inside the Iberostar Waves Tucán in Playacar offering sauna, Turkish bath and jet-pool treatments, open to day-pass visitors 16 and up.

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+.

Tulum, Quintana Roo

A boutique hotel resort in Tulum's Aldea Zama with two pools, a yoga terrace and a rooftop restaurant, open to overnight guests rather than day visitors.

New Orleans, Louisiana

Hotel spa and rooftop wellness deck in New Orleans' CBD with sauna, steam, cold plunge and thermal circuits, restricted to guests 21 and up.

Riviera Maya, Quintana Roo

Beachfront resort spa in Playa del Carmen built around Mayan wellness themes, open to hotel guests only, with yoga sessions and a relaxation lounge.