Spas with upscale

Ibusuki, Kagoshima

A ryokan-style hotel in Ibusuki with source hot-spring baths, both shared and private, open only to overnight guests.

Los Angeles, California

A hotel spa at Shade Hotel Redondo Beach with sauna, steam, pools, cold plunge and thermal circuits, open to hotel guests overlooking the marina.

Jackson Hole, Wyoming

Small hotel spa inside the boutique Rusty Parrot Lodge in downtown Jackson Hole, open only to overnight guests, with massage and facial treatments including

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.

Sayulita, Nayarit

A hillside boutique hotel spa outside Sayulita with sauna, steam room, cold plunge and ocean-view pool, open on a day-pass basis.

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.

Oaxaca

An all-inclusive beachfront resort spa in Huatulco with a sauna, steam room and thermal pools, open only to hotel guests.

Cancún, Quintana Roo

The spa at this all-inclusive Puerto Morelos resort offers hydrotherapy, massages and facials for hotel guests only.

Miami, Florida

A hotel spa at Eden Roc Miami Beach in Mid-Beach with sauna, steam room, cold plunge and thermal circuits, open to resort guests only.

Taos, New Mexico

A boutique skin and body studio in Taos offering facials, lymphatic massage, Endermologie and head spa treatments by appointment.

Kamijima, Ehime

An all-inclusive resort on Yugejima island in Setouchi's inland sea, with ocean-view outdoor baths, ocean-front rooms, and a day-pass option.

Punta Cana, La Altagracia

A hotel spa inside the adults-only JOIA Bávaro by Iberostar beach resort in Punta Cana, open only to overnight guests.

San Diego, California

Hotel spa on Shelter Island in San Diego with sauna, steam room, and pool, open to guests staying at Kona Kai Resort.

Catskills, New York

A Catskills retreat center with a Tibetan-style spa offering sauna, steam, pools and cold plunge, built around overnight stays and group programs.

Kyle, Texas

A 88-acre Hill Country resort near Kyle and Wimberley with overnight rooms, a garden spa, pool, hot tubs and day-pass access by reservation.

San Diego, California

A hotel spa on Mission Bay in San Diego with sauna, steam room, cold plunge and thermal pools, open only to resort guests.

Park City, Utah

Serenity Spa is the treatment center inside Westgate Park City Resort, a ski-in villa resort with a year-round indoor/outdoor pool, sauna and steam room for

Opelika, Alabama

A hotel spa inside the Auburn Marriott Opelika Resort on the Robert Trent Jones Trail golf course, open to hotel guests.

Adairsville, Georgia

A resort spa at Barnsley Resort in Adairsville, Georgia, offering massage, facials, reflexology, sauna and steam room, open to hotel guests only.

Scottsdale, Arizona

A hotel spa at the 65-acre Fairmont Scottsdale Princess resort in North Scottsdale, open to overnight guests with sauna, steam room and pool access.

Atami, Shizuoka

A hotel spa in Atami with a thermal onsen pool, open only to overnight guests staying at Fufu Atami.

Sint Eustatius

A 40-acre dive-and-stay resort on Sint Eustatius with a pool, restaurant and shuttle service to its dive center, open only to overnight guests.

Scarborough

A boutique hillside hotel above Bacolet Bay in Scarborough, Tobago, with an infinity pool and ocean views, built around a converted 150-year-old Donkey Cart

Catskills, New York

Adults-only resort spa in the Catskills with sauna, hot tub, yoga studio and overnight stays for hotel guests only.