Hotel Spa in California

Adults-only hotel spa at the Parker Palm Springs with 15 private treatment rooms, couples suites and a $300 signature aloe treatment.

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

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

Adults-only hotel spa in Sausalito, California, offering day passes alongside yoga and a restaurant on site.

A 25-room Sonoma hotel in Forestville with a spa barn offering sauna, steam and pools, mainly for overnight guests.

A moderately priced fitness-club spa in downtown San Francisco offering bodywork, skincare and specialty treatments with reservations required.