Spas with overnight stay

Palm Springs, California

Hotel spa inside the 16-story Agua Caliente Rancho Mirage casino resort, offering massages, facials and body treatments alongside a pool and hot tub.

Solvang, California

A resort spa inside Alisal Ranch, a 10,500-acre luxury guest ranch in Santa Ynez Valley open only to overnight guests by reservation.

Goa

A resort spa called Prana inside Azaya Beach Resort on Benaulim Beach, open to hotel guests for massage therapies, yoga and poolside workouts.

Carmel-by-the-Sea, California

A resort spa inside Bernardus Lodge in Carmel Valley wine country, open to lodge guests for treatments, yoga and a relaxation lounge.

Mendocino, California

A bluff-top inn on the Mendocino coast offering massages, yoga and sound therapy to overnight guests, with meals included.

Hudson Valley, New York

Hotel spa at a small Hudson Valley inn on 75 riverside acres in Milton, NY, open to overnight guests by reservation while the spa undergoes renewal.

Bük, Vas

A medicinal thermal bath complex in Bükfürdő with pools, a sauna area and on-site accommodation, open daily on a day-pass basis.

Portland, Oregon

Adults-only hotel and thermal springs on NE Alberta St in Portland, with vitality pools, a day-pass option, and spa treatments.

Carson, Washington

A clothing-optional, adults-only mineral hot springs bathhouse in Carson, Washington, with a $12 day pass and a $30 bath-and-wrap treatment.

San Francisco, California

A luxury resort spa at Fort Baker in Sausalito with outdoor baths, open only to Cavallo Point hotel guests.

Santa Cruz, California

A hotel spa on a 300-acre Santa Cruz hilltop with Monterey Bay views, outdoor baths and a relaxation lounge, open only to resort guests.

Jerusalem, Jerusalem District

An adults-only resort spa in the Judean Hills outside Jerusalem, with indoor and outdoor pools, a hammam and a day-pass option.

Tbilisi

A hotel-guests-only private spa in Tbilisi's Chugureti district with a Finnish sauna, Turkish steam room and jacuzzi booked for one party at a time.

Lake Tahoe, California

An 8,500 sq ft spa at Edgewood Tahoe Resort in Stateline, offering massages, facials, couples treatments and an oxygen bar for Tahoe's altitude, open to lodge

Crested Butte, Colorado

A hotel spa inside Elevation Hotel & Spa in Crested Butte, Colorado, open only to overnight guests staying at the slopeside property.

Catskills, New York

A resort spa in Mt Tremper, Catskills, offering treatments, a relaxation lounge and dining, open to both day-pass visitors and hotel guests.

San Diego, California

Adults-only hotel spa in Carmel Valley with sauna, steam, cold plunge and thermal circuits, open to guests of the Fairmont Grand Del Mar.

Riviera Maya, Quintana Roo

Resort spa at the Fiesta Americana Cozumel with sauna, steam room, cold plunge and couples treatments, open to hotel guests only.

Mývatn, Northeastern Region

A 92-room hotel at Lake Mývatn with an in-house sauna for overnight guests only; no day-pass access.

Scottsdale, Arizona

Adults-only resort spa in Scottsdale with sauna, steam, cold plunge and thermal pools, open only to hotel guests.

Bad Ragaz, St. Gallen

Hotel resort spa in Bad Ragaz built around the valley's 36.5°C thermal water, with saunas, pools and treatments open to overnight guests.

Riviera Maya, Quintana Roo

Beachfront all-inclusive resort in Playa del Carmen with a hydrothermal circuit spa available to hotel guests for an extra charge.

Lake Tahoe, California

A resort spa inside Granlibakken's mountain lodging complex near Tahoe City, open to hotel guests with a pool, hot tub and yoga space on site.

Ibiza, Balearic Islands

Hotel spa at a clifftop Ibiza resort, open to overnight guests only, with massages, SkinCeuticals facials and body treatments plus yoga and hiking.