Skydeck Chicago is the breathtaking, thrilling observatory atop the iconic Willis Tower. The highest observation deck in the United States, Skydeck provides views of the city spanning up to four states and 50 miles on a clear day. Skydeck features The Ledge; five glass floor balconies extending 4.3 feet from Willis Tower and made up of three layers of half-inch thick glass laminated into one seamless unit. After an extensive transformation, Skydeck offers a can’t miss, one-stop attraction to discover and see all that the city of Chicago offers from an incomparable vantage point. The revamped attraction features a brand-new, lower-level, museum-like interactive experience that celebrates the unique personality, history, neighborhoods, and sites of Chicago.