Construction of One World Trade Center

Construction of One World Trade Center was deferred until 2006 because of disputes between the Port Authority of New York and New Jersey and the developer. Tishman Realty & Construction is the selected builder. The building reached ground level on May 17, 2008, and was topped out on May 10, 2013. One World Trade Center opened to tenants on November 3, 2014, and One World Observatory opened to the public on May 28, 2015.
One World Trade Center is considered the first major building whose construction is based upon a three-dimensional Building Information Model. The symbolic cornerstone of One World Trade Center was laid down in a ceremony on July 4, 2004, but further construction of the tower was stalled until 2006. The cornerstone was temporarily removed from the site on June 23, 2006. The project was delayed due to disputes over money, security and design but the last major issues were resolved on April 26, 2006 with a deal between developer Larry Silverstein and the Port Authority of New York and New Jersey. During the summer of 2006, explosives were detonated at the World Trade Center construction site, testing the use of charges to clear bedrock for the building's foundation. Controlled explosions continued for approximately two months thereafter.

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