An elegant Gothic-Revival exterior encloses a lavish space with many stories to tell. The building was originally built as the Davis Hotel, then it became the Knickerbocker in the 1930s. Well-known visitors included Presidents Kennedy and Nixon, Muhammad Ali and Daryl Hannah. Hugh Hefner purchased the building in the 1970s and transformed it into the Playboy Hotel. Millennium Hotels undertook an ambitious restoration after acquiring the hotel in 1999. Off the lobby mezzanine is the Prince of Wales, an intimate wood-paneled lounge. The hotel’s most distinctive feature is the Crystal Ballroom. There, a domed, gilded Georgian ceiling is lit from below by Chicago’s only illuminated dance floor.