The buzz around New York's Time Warner Center on Columbus Circle is blaring, but one of the building's hottest spots is, thankfully, an oasis of calm. The Spa at the Mandarin Oriental hotel is a huge, lavish retreat 35 stories above the Manhattan hustle, and it has revitalized the city spa experience. The 14,500-square-foot facility, with bamboo floors and silk wall coverings, employs an entirely customized treatment regimen called a Time Ritual. A two-hour, $200 session begins with a consultation with a therapist who devises, on the spot, a series of treatments drawn from 75 techniques based on Chinese, Balinese, Thai, Japanese, and European traditions. You can also dip into a plunge pool, sit in an amethyst-crystal steam room, take tea in the lounge, or swim in the 75-foot-long lap pool wrapped in floor-to-ceiling windows. For true indulgence, book the Spa Suite, which has a fireplace, twin massage beds, a Kang bed for Thai massage, color-therapy lighting, and a black-tiled whirlpool with spectacular views. Spa suite, $975 for two people for three hours; 212-805-8800.