Spas with cold plunge

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

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

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

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

A hotel spa at Eden Roc Miami Beach in Mid-Beach with sauna, steam room, cold plunge and thermal circuits, open to resort guests only.