The Guerlain Spa (212.872.7200, www.guerlainspa.com) that debuted last September on the 19th floor of New York’s Waldorf-Astoria hotel serves as a sanctuary within the bustling city. The spa has only two common areas, and patrons enjoy treatments in the facility’s 16 private suites. Each suite features a modern design with old-world French elements, a spacious bathroom with a rain shower, and specialty grooming products. All treatments begin in the footbath lounge, where guests fill out a health survey while having their feet cleansed and massaged. Their next step might be the Sublime Deluxe treatment, a roughly eight-hour series of therapies that include a 45-minute hydrotherapy bath, a one-hour body polish, a one-hour complete hand-therapy session, a two-hour antiaging facial, a one-hour body massage, and a lunch prepared by the Waldorf-Astoria kitchen and served in the spa’s relaxation lounge.