Spas with reservation required

Seattle, Washington

A moderate-priced day spa in Bellevue's Wilburton area offering full-body massage and foot reflexology alongside a sauna, steam room and cold plunge.

Tallinn, Harju County

A small hotel spa in central Tallinn with three treatment rooms, two saunas and a Japanese pool, offering massages and facials by appointment.

Seattle, Washington

A two-tank float therapy and infrared sauna studio set inside a ranch house near Kent, Washington, open by appointment only.

Denver, Colorado

A couples-focused massage spa in Auraria, Denver, offering private-room treatments daily from 9am to 9pm with walk-ins accepted.

Vail, Colorado

Hotel spa inside Park Hyatt Beaver Creek with a 5-step hydrotherapy circuit, sauna, steam room and day-pass access to massages, facials and fitness classes.

New York City, New York

Luxury hotel spa inside the Lotte New York Palace on Madison Avenue, offering ila's organic treatments, sauna, steam room and private yoga studio.

Los Angeles, California

A full-service day spa and medspa in Brentwood offering massage, facials, nail care and injectables, with walk-ins welcome and reservations recommended.

Austin, Texas

A full-service day spa in Austin's 2nd Street District offering massage, facials, nails and medspa treatments, open daily 8am to 10pm.

Austin, Texas

Day spa and medspa inside The Loren Hotel by Lady Bird Lake, open to both hotel guests and the public, with massage, facials and injectables.

The Hamptons, New York

A small day spa on Main Street in East Hampton offering HydraFacials, organic facials, laser treatments and massage, with a sauna and relaxation lounge.

Minneapolis, Minnesota

A St. Paul wellness studio in Macalester-Groveland offering infrared sauna, float tanks, salt therapy and cold plunge by reservation, adults-only, day-pass

Tucson, Arizona

A day spa in Tucson's Blenman-Elm district offering massage therapy with hot stones, aromatherapy and cupping included, plus couples sessions.

Los Angeles, California

Day spa in Woodland Hills with a hydrotherapy circuit, massage, facial and body treatment menu, open daily 8am-10pm (closed Tuesdays).

Carefree, Arizona

A 20-plus-acre desert wellness resort in Carefree, Arizona, with a full spa, pools, and 100-plus weekly fitness and mindfulness classes open to day visitors by

San Francisco, California

A Nob Hill facial studio specializing in Biologique Recherche and MBR Cosmetics treatments, with a relaxation lounge for before or after.

San Francisco, California

A boutique day spa in San Francisco's SoMa district offering massage, facials, nails and waxing, plus a retail skincare boutique and relaxation lounge.

San Diego, California

A La Jolla medical spa specializing in lymphatic drainage, colon hydrotherapy and detox treatments, open since 1993, adults only, by reservation.

Colorado Springs, Colorado

A moderate-priced holistic wellness center in West Colorado Springs offering dry salt therapy, massage, yoga and occasional sound-healing or cacao ceremonies.

Houston, Texas

An upscale day spa in Houston's Montrose/River Oaks area offering massage, facials and waxing in private suites, open daily 10am-9pm.

Tampa, Florida

Adult-focused day spa in North Tampa offering facials, massage, waxing, infrared sauna and salt therapy, open daily with walk-ins welcome.

Canggu, Bali

Open-air Balinese day spa on Jl. Pantai Batu Bolong in Canggu, with 38 treatment rooms covering massage, beauty, hair and spa packages.

Denver, Colorado

A reservation-only massage spa in Denver's University Hills offering body, foot and combo massages, with no day-pass option.

Granada, Andalusia

A traditional-style hammam in central Granada with a heated thermal pool and relaxation lounge, open daily from 9am to midnight.

Key West, Florida

Hotel spa at the Hyatt Centric Key West with massages, facials, an infrared sauna with halotherapy, and couples' treatments by reservation.