Architecture of Chicago a new structural system of framed tubes in skyscraper design and construction. The first building to apply the tube-frame construction was the DeWitt-Chestnut Apartment Building which Khan designed and was completed in Chicago by 1966. This laid the foundations for the tube structures of many other later skyscrapers, including his own constructions of the John Hancock Center and Willis Tower (then named the Sears Tower) in Chicago and can be seen in the construction of the World Trade Center, Petronas Towers, Jin Mao Building, and most other supertall skyscrapers since the 1960s. Willis Tower would be the world's tallest building
Tower Building, Liverpool Tower Building, Liverpool Tower Buildings is a former office block in the city of Liverpool, Merseyside, England. It stands with its longer front on the east side of the Strand, and extends round the corner into Water Street. The building is located directly opposite the Royal Liver Building, which was designed by the same architect. Earlier buildings on the site have been a sandstone mansion, and a later fortified house known as the Tower of Liverpool. After this was demolished in 1819, it was replaced in 1846 by the first structure to be named Tower Buildings. The present structure is