Willis Tower, formerly named Sears Tower, is a 108-story 1,450 feet (442 m) skyscraper in Chicago, Illinois. This tallest skyscraper in the United States has four glass box viewing platforms.
Willis Tower, formerly named Sears Tower, is a 108-story 1,450 feet (442 m) skyscraper in Chicago, Illinois. This tallest skyscraper in the United States has four glass box viewing platforms.