Fortress No Longer: What's in Store for Willis Tower

Filling up a block, the forbidding base of Willis Tower (or as diehard Chicagoans would have it, Sears Tower) was designed as a fortification against the street. Fran Spielman writes, "Architects noted that the building once known as Sears Tower was built with the idea of separating the 'urban streetscape' from the building to 'minimize' pedestrian traffic."

Now, with the enthusiastic support of Mayor Rahm Emanuel, the structure will undergo a $500 million renovation to solve that problem and reap retail rewards. As Emanuel put it, "It'll be more receptive to foot traffic for people coming, staying longer and also not going outside the South Loop for lunch. It's gonna be a tremendous draw."

The tower will still be its old monolithic self, but renderings show it perched atop an open, airy retail space. "The plan calls for six levels of restaurant, entertainment and retail space, with three of the floors above ground and three below ground [...] It will include a 30,000-square-foot outdoor deck and garden and a new, three-story transparent glass structure set atop the existing stone plaza."