when did construction start on the twin towers
August 1968
Twin Towers
Construction work began on the North Tower in August 1968 with construction beginning on the South Tower by January 1969.
The North Tower in August 1968 and the South Tower by January 1969. 21 March 1965. Construction work began on the North Tower in August 1968 with construction beginning on the South Tower by January 1969
Construction of the World Trade Center Construction of the World Trade Center Construction of the World Trade Center
Twin Towers Construction Twin Towers
Construction work began on the North Tower in August 1968 with construction beginning on the South Tower by January 1969. In January 1967, $74 million in contracts were awarded to the Pacific Car and Foundry Company, Laclede Steel Company, Granite City Steel Company, and Karl Koch Erecting Company to supply steel for the project. The Port Authority chose to use many different steel suppliers, bidding on smaller portions of steel, rather than buy larger amounts from a single source such as Bethlehem Steel or U.S. Steel as a cost-saving measure. Karl Koch was also hired to do all the work of erecting the steel, and a contract for work on the aluminum facade was awarded to the Aluminum Company of America. Tishman Realty & Construction was hired in February 1967 to oversee construction of the project. n March 1965, the Port Authority began acquiring property at the World Trade Center site. The Ajax Wrecking and Lumber Corporation was hired for the demolition work, which began on March 21, 1965 to clear the site for construction of the World Trade Center. Construction work began on the North Tower in August 1968 with construction beginning on the South Tower by January 1969. 
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Construction of the World Trade Center [SEP] Twin Towers
Construction work began on the North Tower in August 1968 with construction beginning on the South Tower by January 1969. In January 1967, $74 million in contracts were awarded to the Pacific Car and Foundry Company, Laclede Steel Company, Granite City Steel Company, and Karl Koch Erecting Company to supply steel for the project. The Port Authority chose to use many different steel suppliers, bidding on smaller portions of steel, rather than buy larger amounts from a single source such as Bethlehem Steel or U.S. Steel as a cost-saving measure. Karl Koch was also hired to do all the work of erecting the steel, and a contract for work on the aluminum facade was awarded to the Aluminum Company of America.