Willis Tower is stands at 1,450-foot (442.1 m). At completion in 1973, it surpassed the World Trade Center towers in New York to become the tallest building in the world, a title held for nearly 25 years and remained the tallest building in teh Western Hemisphere until 2014 and the completion of a new building at the World Trade Center site. Willis Tower is the second-tallest building in the United States and Western hemisphere and the 16th tallest in the world. The skyscraper is one of the most popular tourist destinations in Chicago, and over one million people visit its observation deck each year. Named the Sears Tower since its opening, the structure was renamed in 2009 by the Willis Group, as part of their lease on a portion of its space. This 3D Puzzle is made of paper and expandable polystyrene foam board, it is easy to assemble without the use of any other tools or glue. No of Pieces: 51. Model Size: 26cm x 19cm x 63cm. Age: 8+ years.