Spas with reservation required

Mexico City, Quintana Roo

A Japanese-style hotel spa in Mexico City's Cuauhtémoc district with tatami suites, outdoor onsen baths and a $2,080 day pass for couples.

Karlovy Vary, Karlovy Vary Region

A one-room beer bath spa in a 18th-century cellar in central Karlovy Vary, with unlimited beer, oak tubs and a straw-bed rest area.

Františkovy Lázně, Karlovy Vary Region

A private beer-bath spa in Františkovy Lázně where you soak in oak tubs with hop and yeast extracts and drink unlimited Krušovice beer.

Ras Al Khaimah

A luxury hotel spa on Hayat Island in Ras Al Khaimah with pearl-shaped treatment rooms and a Turkish Hammam, open daily 10am–7pm by reservation.

Liverpool, New York

A moderate-priced day spa in Liverpool, NY, offering 20 massage-focused treatments plus sauna, steam, cold plunge and thermal pools, open daily 10am–8pm.

Cockeysville, Maryland

A Cockeysville medical day spa blending clinical massage, sauna, steam and thermal pool with reiki, coaching and corrective exercise for chronic pain and

Scottsdale, Arizona

Hotel spa at the Inn at Eagle Mountain in Fountain Hills with sauna, steam room, pools and a $69 60-minute massage as its signature treatment.

Seattle, Washington

Japanese-style head spa in Belltown offering scalp treatments and bodywork from $55, open daily 10am to 10pm, reservations needed.

Sofia, Sofia City

Small day spa near South Park with a heated pool, jacuzzi, Finnish sauna, steam room and a traditional-style hamam, capped at 10 guests.

Colombo, Western Province

A hotel spa inside The Kingsbury Colombo offering Balinese and Thai-style massages, facials and body treatments, with couples packages.

Portland, Oregon

A reservation-only head spa in Vancouver, WA, just across the river from Portland, focused on scalp, face and hand treatments plus a post-service relaxation

Las Vegas, Nevada

Adults-only hotel spa inside Westgate Las Vegas offering massages, facials, salon services, sauna, steam room and a thermal pool, open daily 9am-6pm.

Naples, Florida

A small, moderately priced day spa in East Naples offering massage and a sauna, open daily with walk-ins accepted.

Asheville, North Carolina

A Japanese-inspired destination spa on a mountainside outside downtown Asheville, built around private outdoor salt hydrotherapy tubs and massage.

Sierraville, California

A non-profit hot springs retreat near Lake Tahoe with natural spring pools, reservation-only day and evening soaks, camping and rooms, closed Mondays and

Carmel-by-the-Sea, California

Upscale day spa in Carmel-by-the-Sea's Golden Rectangle with sauna, steam, cold plunge and thermal pools, open daily from 6:30am.

Kyoto

Hotel spa in Kyoto's Higashiyama Ward with a day pass for pool, bathhouse, sauna and gym, plus treatment suites and couples options.

Asheville, North Carolina

A boutique day spa inside Haywood Park Hotel in downtown Asheville, offering facials, massage and couples treatments with free valet parking.

Seattle, Washington

A reservation-only social wellness sauna spa in Renton (serving the Seattle area) with a thermal pool, cold plunge, sauna and steam room, day passes from $75.

Mumbai, Maharashtra

An upscale Ayurvedic retreat in Vile Parle West, Mumbai, with five treatments, couples rooms and a relaxation lounge; reservations required, open daily

Sopot, Pomerania

A medical resort spa in Sopot built around local brine and mud treatments, open to hotel guests by reservation rather than day visitors.

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.

Phuket

A compact day spa on Thalang Road in Phuket Old Town offering rose-petal jacuzzi baths and coconut milk soaks, geared toward couples, open daily 10am–11pm.

Austin, Texas

Adults-only hotel spa at the Fairmont Austin with nine treatment rooms, a hydrotherapy circuit, sauna and cold plunge, open daily with day passes available.