Spas with reservation required

London, England

Thermal bathhouse near Covent Garden in a former J.M. Barrie house, offering multi-temperature pools, massages and couples treatments by reservation.

Toronto, Ontario

A reservation-only thermal bath circuit in a 1912 Edwardian building in Toronto, with eight pools, a dry sauna, steam room and massage treatments.

Santa Fe, New Mexico

A small medical spa in Santa Fe focused on advanced facials, skin rejuvenation and massage, by reservation.

Barcelona, Catalonia

Adults-only thermal baths in a converted 18th-century building near Barcelona's Born market, with soaking pools, massages and couples rituals.

Copenhagen, Capital Region

A thermal-bath spa in Vesterbro, Copenhagen, built around a signature Pediluvium foot-bath ritual plus a relaxation lounge and thermal pool.

Melbourne, Victoria

A Brunswick medical spa pairing traditional Hammam steam rituals with chiropractic care, Endermologie and skin treatments, by appointment only.

Sonoma, California

A Sonoma medical day spa run by a 25-year skincare specialist, offering non-toxic facials, microcurrent and micro-channeling treatments up to $350.

Längenfeld, Tyrol

A large thermal bath and 4-star hotel spa in the Ötztal valley near Längenfeld, with indoor-outdoor pools, a sauna garden and a dedicated kids' water world.

Austin, Texas

Medical spa and day spa on South Lamar offering facials, injectables, massage and a signature $1,499 Mermaid Lift, open daily with private rooms and a stocked

Boston, Massachusetts

A Newbury Street day spa and med spa in Back Bay offering massage, facials, hydrafacials and microneedling, closed Mondays.

Kuala Lumpur

An onsen-style day spa in Kampung Baru, Kuala Lumpur, with thermal pools, sauna, steam room and couples treatments.

Jackson Hole, Wyoming

Rooftop hotel spa at Hotel Terra in Teton Village offering facials and massages, with hot tub and steam room access included only when you book a treatment.

Hot Springs, Arkansas

A combined day spa and med spa in Hot Springs offering massages, facials, laser treatments and lunch-inclusive packages by reservation.

Bad Füssing, Bavaria

Medical spa inside Hotel Mürz in Bad Füssing-Safferstetten, open daily 8am-7pm with walk-in day passes for facials, massage and physiotherapy.

Austin, Texas

A medical spa in Old West Austin offering facials, Botox, fillers, skin tightening and micro-needling, with reservations recommended.

Columbia, Maryland

A luxury medical and day spa in Columbia's Town Center combining facials, massage and laser/injectable treatments with a thermal pool, sauna and steam room.

Denver, Colorado

A medical spa in Thornton offering Japanese head spa treatments, body wraps, chemical peels and B12 shots, with sauna, steam room and pool access.

Orlando, Florida

Medical spa in Orlando offering facials, massage, body contouring and couples packages, with an on-site sauna, steam room and thermal pool.

Dallas, Texas

A Knox/Henderson day spa and medspa in Dallas offering massage, facials and aesthetic treatments, open daily 10am–9:30pm.

Naples, Florida

Adults-only day and medical spa in Old Naples offering massages, facials and monthly Botox/filler visits from Dr. Keamy, with a $155 signature facial.

Berkshires, Massachusetts

A medical spa in downtown Great Barrington offering injectables, lasers, facials and skin treatments by appointment only.

Austin, Texas

Medical spa on Rainey Street in downtown Austin offering Botox, fillers, laser, facials and semaglutide weight-loss care by appointment only.

Atlanta, Georgia

Membership-based medical spa in Buckhead combining aesthetics, massage and facials, and lounge spaces for meditation and recovery.

Santa Fe, New Mexico

A medical spa in downtown Santa Fe offering injectables, laser skin treatments and hormone therapy by appointment, with no walk-in day pass.