Spas with upscale

Minneapolis, Minnesota

Hotel spa inside Hotel Ivy in downtown Minneapolis, offering massages, facials, body treatments and a steam room on the hotel's second floor.

Miami, Florida

A beachfront resort spa in North Beach, Miami with cryotherapy, a floating salt bath, sauna, steam and a cold plunge, open to walk-ins and day-pass guests.

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.

Jackson Hole, Wyoming

A day spa next to the Trailborn hotel in Jackson Hole with an outdoor pool deck, salt lounge and day passes for walk-in soaks or treatments.

Houston, Texas

Day spa in Houston's Westside with a grotto pool, outdoor pool, steam rooms and sundeck, plus an on-site restaurant; walk-ins welcome.

The Hamptons, New York

Oceanfront resort spa in Montauk with a seawater and marine-based treatment menu, hydrotherapy, contrast bathing, and a heated saltwater pool.

Doha

Hotel spa at The Westin Doha with some of the city's largest wet facilities, accessible to hotel guests and members only, no day passes sold.

Opatija, Primorje-Gorski Kotar

A 5-star hotel spa in Opatija with a sauna centre, seawater pools and couples treatments, open only to Hotel Ambasador guests.

Velingrad, Pazardzhik

Hotel spa in Velingrad with mineral-water pools, saunas, steam rooms and a hammam spread over 4,000 square metres; day passes are available.

Chicago, Illinois

Day spa in Burr Ridge, about 20 miles outside Chicago, built around a hydrotherapy circuit with whirlpool, cold plunge and steam room.

Ein Bokek, Southern District

Hotel spa on the Dead Sea shore in Ein Bokek with a heated mineral-water pool, sulphur pools, hammam and sauna; day passes open to adults 16 and up.

San Francisco, California

Neighborhood day spa in Noe Valley with a private outdoor hot tub, offering massage and a combined soak-and-massage package for two.

Honolulu, Hawaii

A beachfront Waikiki hotel with a pool, fitness center and yoga sessions, open to guests staying at the OUTRIGGER Reef.

Edinburgh, Scotland

One Spa is an adults-only day spa in Edinburgh's city centre with a rooftop Hydropool, thermal suite and day-pass access.

Park City, Utah

A 14-room hotel spa at Westgate Park City Resort with a waterfall, sauna, steam room and thermal pools, open daily 9:30am-6:30pm.

Napa Valley, California

Hotel day spa atop the Archer in downtown Napa with a water deck, fitness studio access and treatment rooms; reservations required.

Sirmione, Lombardy

A lakeside thermal spa in Sirmione with indoor and outdoor pools fed by sulphurous spring water, a vascular circuit, saunas, and a day-pass option.

Scuol, Grisons

Hotel spa at the 4-star Belvedere in Scuol with indoor/outdoor pools, mineral and thermal water, sauna, steam bath and a day pass option.

Vienna

Hotel spa in Vienna's Neubau district with a 20-metre indoor pool, two saunas, a steam room and day passes for non-guests.

Asheville, North Carolina

A Japanese-inspired destination spa on a mountainside outside downtown Asheville, built around private outdoor salt hydrotherapy tubs and massage.

Auckland

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

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.

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

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