Spas with reservation required

San Francisco, California

Adults-only Russian bathhouse in San Francisco's India Basin with steam rooms, cold plunge, rooftop deck and a café, open daily except Tuesday.

Las Vegas, Nevada

Adults-only hotel spa at Resorts World Las Vegas with a six-pool hydrotherapy circuit, salt room, and a themed Aufguss sauna show on weekends.

Palm Springs, California

Adults-only hot springs resort on Miracle Hill in Desert Hot Springs with private mineral tubs, a Finnish sauna, salt room and 35 spa treatments.

Plainfield, Indiana

Day spa in Plainfield, IN offering facials, massages and body-sculpting treatments alongside a sauna, steam room and thermal pool, reservation required.

Indianapolis, Indiana

Two Indianapolis locations for cryotherapy, infrared sauna, Normatec compression and float therapy, with walk-ins welcome.

Nashville, Tennessee

A Brentwood day spa focused entirely on scalp and head treatments, with private suites and a signature ritual built around halo water therapy.

New York City, New York

Hotel spa inside Thompson Central Park combining massages, facials and body treatments with daily fitness classes and private saunas, near Central Park.

Seattle, Washington

A Bellevue day spa in Wilburton specializing in head spa scalp treatments, massage, facials and couples sessions, with free on-site parking.

Los Angeles, California

A women-focused Korean day spa in Pico-Union with steam, salt and ice rooms, open daily 9am to 9pm, with massage and facials open to men too.

Scottsdale, Arizona

A moderately priced day spa in South Scottsdale with lake-view suites, massage and facials, plus a dedicated couples treatment room.

Miami, Florida

A Peruvian-themed day spa inside the Victor Hotel on Ocean Drive, South Beach, with a hamam, steam room, sauna and a couples suite.

Miami, Florida

Nature-themed day spa in Brickell with hydro massage, a hydrotherapy circuit and couples treatments, open daily 9am-6pm.

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.

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.

Sedona, Arizona

A moderately priced day spa in Sedona with outdoor gardens, a hot tub and fountains, known for its Prickly Pear Pomegranate body treatment.

Palm Springs, California

Adults-only hotel spa at Tommy Bahama Miramonte in Indian Wells with 15 treatments, eucalyptus steam rooms, a hydrotherapy jacuzzi and saltwater pool.

Calistoga, California

Spa Talisa is the adults-only spa at the Four Seasons Resort Napa Valley in Calistoga, with vineyard-view gardens, barrel saunas and a sunken whirlpool for

Napa Valley, California

Adults-only resort spa built into a wine cave in Napa, with a vineyard-view pool, sauna, steam room and hot tub; reservations required.

Naples, Florida

Upscale day spa in Naples offering infrared sauna, massage, facials and foot detox, with a $230 signature massage and couples packages.

Marana, Arizona

Adults-only hotel spa at Dove Mountain Resort in Marana with desert-themed treatments, an infinity-edge pool, sauna and steam room; facility access comes with

Lake Tahoe, California

A 17-room, adults-only hotel spa at Lake Tahoe's Ritz-Carlton with a heated lap pool, sauna and steam room; day pass access requires booking a treatment.

Scottsdale, Arizona

Resort spa at Camelback Inn in Scottsdale with 20 treatment rooms, a thermal circuit and day-pass access open to non-guests.

San Diego, California

Adults-only hotel spa in Carmel Valley with a hydrotherapy circuit, two fireplace lounges, and a $100 day pass covering pools and fitness facilities.

San Diego, California

Resort spa on Mission Bay offering massages, facials and body treatments, with walk-ins welcome and a gym and yoga classes on-site.