The city of Chicago has always been an architectural trendsetter–after all, it’s where the skyscraper was invented. And there’s nowhere better to soak in that history–and some truly breathtaking birdseye views–than the recently renovated Skydeck Chicago atop the commanding Willis Tower. Formerly known as the Sears Tower, the Willis held the title of tallest building in America for decades (it was only recently dethroned by New York’s Freedom Tower). Adrenaline junkies won’t want to miss The Ledge–a series of four all-glass balconies dramatically suspended thousands of feet up over the street. What sort of wonders can one spy from 1454 ft? On a clear day, more or less everything–every corner of Chicago, all the way across the Illinois state line into Indiana, Wisconsin, and Michigan.