Spas with upscale

New York City, New York

Adults-only day spa on Governors Island with heated outdoor pools, saunas and an Italian-style café, reachable by ferry from Manhattan.

Las Vegas, Nevada

Hotel spa inside Caesars Palace in Las Vegas with a hydrotherapy circuit and relaxation lounge, open daily 9am–6pm for hotel guests.

Aachen, North Rhine-Westphalia

Adults-only day spa in Aachen with a hydrotherapy circuit and relaxation lounge, open daily 10am–9pm, upscale pricing.

Bangkok

Hotel spa at SO/ Bangkok on Sathorn Road offering facial, body and beauty treatments plus rooftop infinity pool and fitness access, hotel guests only.

Shibu Onsen, Nagano

A ryokan in Shibu Onsen with indoor and outdoor hot-spring baths fed by two blended mineral springs, open only to overnight guests.

Scottsdale, Arizona

A hotel spa at Scottsdale Camelback Resort, open only to resort guests staying in the property's villas at the base of Camelback Mountain.

Scottsdale, Arizona

An adults-only hotel spa in Old Town Scottsdale with sauna, steam room, cold plunge and thermal pools, open to hotel guests 21 and up.

Goa

A hotel spa inside Sea Queen Beach Resort on Colva Beach, Betalbatim, Goa, open to overnight guests with one signature treatment called The Sea View.

Tyrol, Bavaria

Hotel spa in Kreuth-Reitrain near Tegernsee with a 3,000 sqm onsen-style bathing area, hot and cold pools, saltwater pools and sauna, open on a day-pass basis.

Las Vegas, Nevada

Hotel spa and fitness center at The LINQ in Las Vegas with steam room and sauna, open daily 9am–5pm, day passes available.

Aachen, North Rhine-Westphalia

A suite hotel in central Aachen where each private room has its own jacuzzi and sauna, booked by the night rather than a day pass.

Punta Cana, La Altagracia

Adults-only all-inclusive resort spa in Bávaro with a gym, sauna and couples treatment rooms, open to hotel guests aged 18 and up.

Pagosa Springs, Colorado

A mobile container-trailer spa in Pagosa Springs offering infrared sauna and cold plunge contrast therapy, adults only, by reservation.

Dallas, Texas

Hotel spa inside The Highland Dallas in Lower Greenville, Dallas, with a sauna, steam room, outdoor pool and couples treatment rooms.

Carlsbad, California

Adults-only hotel spa in Carlsbad with steam room, separate men's and women's lounges, and couples massage as its signature treatment.

Sedona, Arizona

Hotel-only spa amenities at The Joy Sedona, a B&B and creekside cabin property near Uptown Sedona with outdoor hot tubs, a relaxation lounge and private suites.

Lake Tahoe, California

Hotel-only spa at a lakefront resort in South Lake Tahoe, with an outdoor heated pool, Jacuzzi and treatment rooms aimed at couples.

Tiberias, Northern District

Adults-only boutique hotel spa on the Sea of Galilee in Tiberias, set in a former hospital building, with a seasonal pool and couples' treatments.

Scottsdale, Arizona

Hotel spa at The Scott Resort offering massages, facials and restorative treatments for guests amid palm-lined grounds in South Scottsdale.

Carmel-by-the-Sea, California

A hotel spa at Sanctuary Beach Resort in Marina, with three treatment rooms, a relaxation lounge and an outdoor deck looking over the dunes and Pacific.

Napa Valley, California

Adults-only resort spa in Napa Valley with pools, sauna, steam and a fitness center, open to hotel guests and club members via day pass.

Edinburgh, Scotland

Hotel spa inside The Caledonian on Princes Street with a thermal pool, sauna, steam room and relaxation lounge, open daily 6am to 9pm.

San Diego, California

Hotel spa at The Lodge at Torrey Pines in La Jolla, with ocean-facing treatment rooms near the Torrey Pines State Natural Reserve, open daily 8am–6pm by

Guerneville, California

Hotel spa at West Sonoma Inn & Spa in Guerneville, open to overnight guests for massages, facials and a vineyard-view lounge.