Spas with upscale

Day spa in the Sherry Frontenac Hotel's lower lobby in Miami Beach, with sauna, steam, cold plunge and thermal pool alongside massage treatments.

An upscale day spa on Miracle Mile in Coral Gables with sauna, steam room and cold plunge, known for a $200 signature treatment and couples packages.

Hotel day spa atop the Archer in downtown Napa with a water deck, fitness studio access and treatment rooms; reservations required.

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

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

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.

Adults-only hotel spa in downtown Napa with thermal circuits, sauna, steam and cold plunge, plus massages, facials and medical aesthetics.

East Town Spa in Milwaukee's Juneau Town combines a full-service salon and med spa with a thermal circuit of sauna, steam, pools and cold plunge.