Spas with relaxation lounge

Palm Springs, California

Hotel spa at Agua Caliente Rancho Mirage with day passes for the sauna, steam room, salt rooms and private spa pool.

Santa Barbara, California

A 42,000-square-foot hotel spa in Santa Barbara with an adults-only pool, redwood sauna, eucalyptus steam room, cold plunge and rooftop terrace.

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

New York City, New York

Korean jjimjilbang-style spa in Manhattan with saunas, steam room, soaking tub and body scrubs, open daily 8am-11:30pm on a day-pass basis.

Santa Ynez, California

Adults-only resort spa inside Chumash Casino Resort in Santa Ynez with 21 treatments, a mineral pool, cold plunge and couple's suites.

Calistoga, California

Hotel spa in downtown Healdsburg with a garden patio, jacuzzi and pool access, open daily 9am-5pm for guests and day visitors.

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.

Napa Valley, California

Adults-only hotel spa in Napa Valley with a co-ed thermal circuit of sauna, steam room and cold shower, open daily 10am–6pm; day passes available.

Palm Springs, California

A 38,000-square-foot resort spa at JW Marriott Desert Springs in Palm Desert offers day passes, saunas, a saltwater lap pool and couples suites.

Tucson, Arizona

Six-room hotel spa at Hacienda del Sol in Tucson, open daily 9-6, taking both resort guests and local walk-ins for massages, facials and body treatments.

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.

San Diego, California

Adults-only day and hotel spa in Rancho Bernardo with gardens, whirlpools, a steam room and an 18-treatment menu, open daily 9am-6pm.

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+.

Sedona, Arizona

Adults-only resort spa in Sedona with outdoor hot tubs, steam rooms and a 30-treatment menu, open daily with walk-ins and day passes.

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.

Houston, Texas

Luxury day spa near Houston's Galleria with massage, facial and body treatments, a salt room and infrared sauna; reservations only, no walk-ins.

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.

Seattle, Washington

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

Puerto Vallarta, Jalisco

A hotel spa inside the beachfront Buenaventura Grand Hotel in Puerto Vallarta, open to resort guests for massage and relaxation between beach days.

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.

Calistoga, California

Day spa and fitness club in St Helena with massage treatments, a heated lap pool and a gym, offering day passes and welcoming walk-ins.