Spas with relaxation lounge

Los Angeles, California

Four Seasons hotel spa in Beverly Hills with a steam room, rooftop pool, fitness center and eight treatments, open daily, day passes available.

Houston, Texas

A Four Seasons hotel spa in downtown Houston with three treatment rooms, a couples' suite and rooftop pool access, open to day-pass guests.

Milan, Lombardy

A luxury hotel spa inside Four Seasons Hotel Milano with a 14-metre pool under a vaulted ceiling, sauna, gym and private suites for couples' treatments.

Vail, Colorado

A hotel spa at Four Seasons Vail with sauna, steam room, whirlpool and ten treatments, open to resort guests only, no day passes.

Vail, Colorado

A day spa and recovery club in downtown Vail with hot tub, sauna, steam room, cold plunge and salt lounge, plus day passes and fitness access.

Chicago, Illinois

A 5th-floor day spa inside the Palmer House Hilton in the Loop, built around a hydrotherapy circuit, Vichy shower treatments and a facial called Glow Revival.

Las Vegas, Nevada

Hotel spa on the Palms casino level in Las Vegas with steam rooms, saunas, a seasonal pool and 32 treatments including massage, facials and body work.

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.

Calistoga, California

A 20-treatment hotel day spa in Santa Rosa with an indoor caldarium plunge pool, eucalyptus steam rooms, and walk-in or reserved day passes for adults 18+.

San Pedro de Atacama, Antofagasta

A hotel spa inside the luxury Tierra Atacama lodge near San Pedro de Atacama, with indoor and infinity pools, sauna, steam room and treatment rooms, open only

Miami, Florida

Hotel spa at The Setai in Miami Beach with 7 ocean-view treatment rooms, 5 couples suites, saunas, steam and a cold plunge.

Los Angeles, California

Day spa in West Hollywood with wet and dry banyas, pool, sauna, cold plunge and café; day pass is $110, walk-ins welcome.

Los Angeles, California

A 24-hour Korean jjimjilbang on Wilshire Blvd in Westlake with single-sex bathing floors, a family-friendly sauna level and a rooftop terrace.

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.

Noboribetsu, Hokkaido

A plain neighborhood bathhouse in Noboribetsu, Hokkaido, offering 100% source-fed hot spring water in two mineral varieties, about 10 minutes from the station.

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.

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

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.

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.

Palm Beach, Florida

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

Palm Springs, California

Boutique hotel spa in Desert Hot Springs with two natural mineral hot spring pools, day passes, and overnight rooms that include breakfast.

Philadelphia, Pennsylvania

Hotel spa on the third floor of The Rittenhouse overlooking Rittenhouse Square, with massage, facials, body treatments and a salon.

Elkridge, Maryland

A halotherapy day spa in West Elkridge, near Baltimore, built around a salt cave, massage rooms and a yoga studio, aimed at solo adult visitors.

Scottsdale, Arizona

A hotel spa at Four Seasons Scottsdale at Troon North offering massages, facials, a full salon and 24-hour fitness access, guests only.