A formal groundbreaking ceremony in Lower Manhattan marked the beginning of the original World Trade Center, one of the most ambitious commercial real estate and urban redevelopment projects of the twentieth century. The Port Authority of New York and New Jersey records 4 August as the official groundbreaking date, while the National September 11 Memorial & Museum notes that construction activity began the following day. Together, these dates mark the launch of a development that would dramatically alter New York’s skyline, business geography and approach to high-density commercial construction.

The project occupied a 16-acre site near the Hudson River in an area previously known as Radio Row, a district filled with electronics shops and small businesses. The redevelopment required land assembly, demolition and the creation of a large urban superblock. It became an important example of how major urban projects could generate economic opportunity while simultaneously raising questions about displacement, compulsory acquisition and the loss of established neighbourhoods.

Architect Minoru Yamasaki, working with Emery Roth & Sons, designed the complex around two 110-storey towers. When completed, the Twin Towers provided nearly 10 million square feet of office space and became home to banks, trading companies, public agencies and international businesses. For a brief period, they were also the tallest buildings in the world, turning the development into a powerful symbol of modern commerce and engineering ambition.

Building on landfill beside the Hudson created exceptional technical challenges. Foundations had to reach bedrock about 70 feet below street level. Engineers used the slurry wall method on an unprecedented scale in the United States, creating an underground barrier that held back groundwater while excavation continued. More than one million cubic yards of soil and rock were removed, with much of the material later used to help create Battery Park City.

The North Tower was completed in December 1970 and the South Tower in July 1971, while the complex was formally dedicated in April 1973. Although the original buildings were destroyed on 11 September 2001, the 4 August 1966 groundbreaking remains a major date in real estate history. It represents the enormous possibilities of coordinated planning, finance and engineering, while reminding cities that megaprojects must be judged by their social as well as economic impact.