Spas with relaxation lounge

The Colony, Texas

A day-soaking spa in The Colony with mineral pools at varying temperatures, seven saunas, cold plunges and a poolside café.

San Diego, California

Korean-style day spa in Kearny Mesa with red clay and salt saunas, hot and cold tubs, an ice room, and walk-in day passes.

Houston, Texas

Hotel spa at Hotel ZaZa in Houston's Museum District, with massages, body treatments, infrared saunas and day-pass access to the pool lounge.

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.

Atlanta, Georgia

A hotel spa and wellness club inside Loews Atlanta Hotel in Midtown, built around hammam, sauna, steam room and a monthly membership rather than drop-in visits.

Boston, Massachusetts

A hotel day spa at Battery Wharf in Boston's North End with a co-ed Turkish hammam, separate saunas, and fitness studios for barre and yoga.

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.

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.

Amalfi Coast, Campania

Hotel spa inside a former 13th-century monastery in Amalfi, with hammam, couple rooms and sauna, open to guests only.

Boston, Massachusetts

Hotel spa inside the Omni Boston Hotel at the Seaport, with eight treatment rooms and a rooftop pool, open to hotel guests only.

Osprey, Florida

Hotel spa and pool deck at a moderate-price resort in Osprey, Florida, with sauna, steam room and thermal circuits for overnight guests.

San Diego, California

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

Key West, Florida

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

Chicago, Illinois

Upscale day spa in Lincoln Park, Chicago, where booking any treatment unlocks all-day access to a hydrotherapy circuit, thermal suite and outdoor terrace.

San Francisco, California

Oakland float and sauna studio near Grand Lake with private float tanks, infrared sauna cocoons and cryotherapy, open daily 11am-8:30pm.

Koh Phangan, Surat Thani

Day spa in Ban Tai, Koh Phangan, with massages, baths and multi-hour packages for solo guests or couples, plus private suites and a sauna.

Seattle, Washington

A med spa and beauty bar inside Seattle's Fairmont Olympic Hotel, open daily with facials, injectables, massage and nail services by appointment.

Chicago, Illinois

A West Town day spa built around a beer soak, with sauna, steam room, salt room and thermal pool for couples or solo visits.

Palm Beach, Florida

A Juno Beach day spa with sauna, steam room and pool, offering massages, facials and couples treatments since 2008.

Tucson, Arizona

A resort day spa at Westward Look in Tucson with a thermal pool, sauna, steam room and cold plunge, open daily 9am-6pm by reservation.

Rocky River, Ohio

Massage-focused day spa in Rocky River offering couples treatments, sauna, steam room and thermal pool, open daily by appointment.