Spas with upscale

Palm Springs, California

Adults-only hot springs resort on Miracle Hill in Desert Hot Springs with private mineral tubs, a Finnish sauna, salt room and 35 spa treatments.

Napa Valley, California

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

Palm Springs, California

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

Kyle, Texas

A 88-acre Hill Country resort near Kyle and Wimberley with overnight rooms, a garden spa, pool, hot tubs and day-pass access by reservation.