Chicago Many other architects have left their impression on the Chicago skyline such as Daniel Burnham, Louis Sullivan, Charles B. Atwood, John Root, and Helmut Jahn. The Merchandise Mart, once first on the list of largest buildings in the world, currently listed as 44th-largest (), had its own zip code until 2008, and stands near the junction of the North and South branches of the Chicago River. Presently, the four tallest buildings in the city are Willis Tower (formerly the Sears Tower, also a building with its own zip code), Trump International Hotel and Tower, the Aon Center (previously the Standard
Joshua Sears Building works on what is now Peter Kirk Park. The building originally intended to house a bank at the corner. Sears outfitted the entire interior and even hired a partial staff but with the arrival of the Panic of 1893, the doors, like the steel mill, never opened. In the years after the bust, the building, like many others in the area remained mostly vacant, though it, along with a large portion of the original townsite remained in the ownership of the Sears estate. The corner space was eventually occupied by a printing company and later a grocery store. An electric