It's called the Windy City for a reason. When the town rebuilt after the 1871 fire, it was set up as a grid, resulting in man-made wind tunnels that pull strong air streams off Lake Michigan and down The Loop, lifting skirts, stealing hats, and swirling dust and debris along the streets. The population of metropolitan Chicago is nearly ten million, making it the third largest city in the world and home to more than half the people of Illinois. It's also home to several professional sports teams, the 110-story Sears Tower (now called "Willis Tower"), historic Navy Pier, great shopping, breathtaking skylines, and lakeside beaches.