7 South Dearborn was a planned skyscraper in Chicago, United States. Located at the intersection of Madison and Dearborn, the building would have been high, with twin antennas pushing the height to exactly . The building would have been the tallest building in the Western Hemisphere at the time, if it were constructed. Initial plans Plans for the 112-story building were announced in 1999 by Scott Toberman of European-American Realty. This would have been the tallest in Chicago at 1,567 feet (478m), surpassing the Willis Tower by . It would also have taken the title for world's tallest building, being taller than the Petronas Towers. A set of three broadcast antennas (not included in the official height) would have brought the total height of the structure to . The site The building took the site of the First Federal Building, a , 18-story Classical office building designed in 1902 by Holabird & Roche. This building housed the offices of the Chicago Tribune until 1925, when the Tribune Tower was built. The building remained until 1999, when European-American Realty acquired the property and demolished it in preparations for 7 South Dearborn. Uses and size 7 South Dearborn would have been mixed-use, with 11 stories of retail and parking at the base, providing 800 spaces of parking, followed by . of office space on 32 floors, then 360 residential units on 43 floors, topping out with of communications facilities on 13 floors. 4 floors of basement and 9 mechanical floors bring the total to 112 floors. Engineering This building represented a major departure from convention by having a big height with small floorplates. This was made possible by a stayed-mast structural system in which columns around the perimeter ("stays") are linked radially to the core by multi-story trusses ("spreaders") at two points along the tower's shaft. The residential and communications floors would have been cantilevered out from the central core, to avoid perimeter columns and maximize views. History In September 1999, the Chicago City Council approved the project. In October 1999, Donald Trump offered to join European-American Realty in the project. European American Realty is a company managed by Scott Toberman, Harold Gootrad and the French Pierre Picard. They declined, so Trump began looking for other sites to invest in Chicago. Later, his efforts would culminate in the construction of Trump Tower Chicago, which used a design that borrowed much from 7