Spas with upscale

Sonoma, California

A boutique day spa in downtown Sonoma centered on infrared sauna and cold plunge drop-ins, plus massage, red light and PEMF therapy.

Sopot, Pomerania

A medical resort spa in Sopot built around local brine and mud treatments, open to hotel guests by reservation rather than day visitors.

Auckland

Hotel day spa at Pullman Auckland CBD with a 25m heated pool, sauna, steam room, jacuzzi and gym plus massage and facial treatments.

Austin, Texas

Adults-only hotel spa at the Fairmont Austin with nine treatment rooms, a hydrotherapy circuit, sauna and cold plunge, open daily with day passes available.

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.

Las Vegas, Nevada

Spa Aquae is JW Marriott Las Vegas Resort & Spa's day spa in Summerlin, with 18 treatments, couples massages and a steam room, open daily 8am-7pm.

Palm Springs, California

Hotel spa at the Renaissance Esmeralda in Indian Wells offering desert-inspired treatments, a recovery lounge, steam rooms and day passes, adults only.

Chamonix, Auvergne-Rhône-Alpes

Hotel spa at Heliopic Chamonix with an ice cave, cold-water well, hammams, sauna and a 15m pool facing the Mont Blanc massif, open to day visitors who book a

Aix-les-Bains, Auvergne-Rhône-Alpes

An upscale day spa inside Hotel Le Riviera in Aix-les-Bains, with pools, saunas, a hammam and eight treatment rooms open to walk-ins.

Austin, Texas

Hotel spa at Hotel Viata in West Lake Hills with treatment rooms, a couples suite, pool, sauna, steam room and a day-pass option for amenity access.

Dubrovnik, Dubrovnik-Neretva

Hotel spa near Lapad Bay in Dubrovnik with a salt room, Finnish and infra saunas, a relaxation lounge, and a nine-treatment menu open daily.

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.

Austin, Texas

A fifth-floor hotel spa inside JW Marriott Austin with eight treatments, a heated rooftop pool and a 16-plus minimum age.

San Diego, California

Adults-only hotel spa at Kona Kai Resort on Shelter Island with six treatment rooms, a couples' suite and day-pass access for non-guests.

Jackson Hole, Wyoming

Resort spa at Teton Village with pools, soaking tubs, a rooftop hot tub, and facials built for Jackson Hole's dry alpine air.

Kissimmee, Florida

A hotel spa at Margaritaville Resort Orlando in Kissimmee with massages, facials and a Himalayan salt room; open daily, walk-ins welcome.

Quebec City, Quebec

A riverside Nordic spa in Old Quebec with an infinity pool, salt-water floating bath and thermal baths along the St. Lawrence, open daily 9am-10pm.

Palm Springs, California

Hotel spa at Agua Caliente Rancho Mirage with day passes for the sauna, steam room, salt rooms and private spa pool.

London, England

A Russian-style banya bathhouse in Belgravia offering oak-lined steam rooms, cold plunge pools and leaf-massage rituals, with day passes by reservation only.

Miami, Florida

A 12,000-square-foot hotel spa at Coral Gables' Biltmore, with eucalyptus steam rooms, Himalayan salt saunas and a couples suite; adults-only, reservation

Ocala, Florida

A hotel spa inside Ocala's AAA Four Diamond Equestrian Hotel, offering couples treatments alongside a fitness center and zero-entry pool.

Miami, Florida

AVEDA hotel spa at The Palms in Mid-Beach Miami, offering Ayurvedic-inspired massages, facials and salon services with pool and beach access included.

Santa Ynez, California

Adults-only resort spa inside Chumash Casino Resort in Santa Ynez with 21 treatments, a mineral pool, cold plunge and couple's suites.

Calistoga, California

Hotel spa in downtown Healdsburg with a garden patio, jacuzzi and pool access, open daily 9am-5pm for guests and day visitors.