Spas with cold plunge

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.

Tucson, Arizona

A luxury all-inclusive wellness resort in Tucson's Hidden Valley with four pools, a hydrotherapy circuit, cold plunges and over 200 spa treatments.

Napa Valley, California

Resort spa at Stanly Ranch in Napa Valley offering hyperbaric oxygen therapy, cold plunge, sauna, steam room and salt therapy, with day passes available.

Duluth, Georgia

A 24-hour Korean bathhouse in Duluth with a $30 day pass, sauna rooms, cold plunge, thermal circuits and a junior Olympic pool.

Chicago, Illinois

A 24-hour Korean bathhouse and sauna complex in Niles near Chicago, with 11 heat rooms, hot and cold pools, and a $45 day pass covering walk-in access.

Los Angeles, California

Women-only Korean day spa in Koreatown, LA with saltwater, mineral and cold pools, a salt room, and walk-in day passes.

Los Angeles, California

Women-only Korean spa and sauna in Koreatown with a $25 day pass, body-scrub massages and clothing-optional bathing areas.

Indianapolis, Indiana

A moderate-priced day spa in northwest Indianapolis offering float therapy, salt room sessions, infrared sauna, cold plunge and foot detox, closed Mondays.

Santa Barbara, California

A downtown Santa Barbara day spa built around a private infrared sauna, salt room, cold plunge and a sound-and-light meditation pod, booked by appointment.

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.

Scottsdale, Arizona

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

Calistoga, California

A 20,000-square-foot resort spa in Calistoga with five geothermal pools, Calistoga mud treatments, and a day pass for non-hotel guests.

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.

Scottsdale, Arizona

Adults-only hotel spa at the Fairmont Scottsdale Princess with a rooftop pool, grotto waterfall pool, sauna, steam room and cold plunge, open daily 6am-7pm.

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.

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

Koh Samui, Surat Thani

Kamalaya Koh Samui is an adults-only destination spa and wellness retreat on Laem-Set Rd with over 100 treatments, thermal circuits and multi-day health

Santa Barbara, California

A reservation-based day spa in downtown Santa Barbara built around private infrared sauna, salt room and cold plunge sessions.

South Jordan, Utah

A day spa and wellness center in South Jordan, Utah, with a salt room, infrared sauna, cold plunge, float therapy and a yoga studio.

Ubud, Bali

An adults-only wellness retreat on Ubud's Ayung River offering multi-day healing programmes, thermal circuits and plant-based cuisine by reservation only.

New Orleans, Louisiana

Hotel spa and rooftop wellness deck in New Orleans' CBD with sauna, steam, cold plunge and thermal circuits, restricted to guests 21 and up.

Miami, Florida

Hotel spa deck in downtown Miami with sauna, steam room, cold plunge and thermal pools overlooking Biscayne Bay, day passes from $50.

Chiang Mai, Northern Thailand

A hotel spa inside the Four Seasons Resort Chiang Mai in Mae Rim, with sauna, steam room, cold plunge and thermal pools set among rice paddies, open to resort