Think of it as a playground for grown-ups. The north end of Michigan Avenue, nicknamed the Magnificent Mile, is a fun, hip and often dazzling thoroughfare, with its rich amalgam of commerce, hospitality, history and architecture. It’s a splendid area for shopping, with Nike Town, Crate and Barrel, Tiffany’s, Bloomingdales, Banana Republic, the Sony Store, Burberry, Hammacher Schlemmer, Neiman-Marcus, and a cluster of high-rise, high-end malls at the north end. Some of the city’s best hotels are found along this stretch, as well as a wide range of dining options, from gloriously upscale to fun and funky. But in this town that created the world’s first skyscraper and gave birth to American architecture, there is more to look at than store windows. Landmark buildings stretch the full length of this great avenue, with architecture that ranges from Italian Renaissance to Art Deco to glass and steel modern. And right at the head of the street, standing like a lighthouse at the end of a sea of cars, is the old Water Tower, survivor of the Great Chicago Fire.