Spas with solo travelers

Day spa in Sacramento's Oak Park with float rooms, private cold plunge and sauna suites, infrared sauna, and a Somadome meditation pod.

A Brentwood day spa focused entirely on scalp and head treatments, with private suites and a signature ritual built around halo water therapy.

A resort spa in Tucson's Starr Pass area with a saline lap pool, sauna and fitness center, plus signature treatments from $159 for hotel guests.

North Scottsdale day spa with massage, facials, sauna, steam and a thermal pool, plus private suites for couples and groups.

A no-frills, family-run day spa on Indian Canyon Dr offering walk-in massage and foot reflexology from $40, open daily until 10pm.

Day spa in Columbia-Tusculum, Cincinnati, with massage, facials, an infrared/Himalayan salt sauna and a $99 signature sampler package.

A Houston day spa near Memorial Park offering massage, facials and spa packages, with a sauna, steam room and pool on site.

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

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.

A St. Paul wellness studio in Macalester-Groveland offering infrared sauna, float tanks, salt therapy and cold plunge by reservation, adults-only, day-pass

A West Town day spa built around a beer soak, with sauna, steam room, salt room and thermal pool for couples or solo visits.

A themed-suite day spa in Seattle's SODO district offering massages, facials, couples packages and a few overnight suites.

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.

A wellness center in Springboro, Ohio built around a natural salt cave, with energy healing, sound baths and metaphysical classes for individuals or groups.

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

A Clairemont wellness studio in San Diego pairing acupuncture and bodywork with an infrared sauna and a Himalayan salt room for classes.

A North Royalton day spa built around a salt room and sauna, with adults-only halotherapy sessions on a walk-in or reserved basis.

A hillside boutique hotel spa outside Sayulita with sauna, steam room, cold plunge and ocean-view pool, open on a day-pass basis.