The 218-foot tall South Air Traffic Control Tower (ATCT) at O’Hare International Airport features two main components, a 13 level ATCT and a 10,000-square-foot base building. The ATCT includes an octagonal control cab measuring 450 square feet. The new tower is a key component of the City of Chicago’s reorganization of the airport to establish a parallel runway system instead of the crisscross layout currently in place.