<P> The core of the complex was built between 1975 and 1985, with a cost of $400 million (equivalent to $1.86 billion in 2016). The World Trade Center experienced a fire on February 13, 1975, a bombing on February 26, 1993, and a bank robbery on January 14, 1998 . In 1998, the Port Authority decided to privatize the World Trade Center, leasing the buildings to a private company to manage, and awarded the lease to Silverstein Properties in July 2001 . </P> <P> On the morning of September 11, 2001, Al - Qaeda - affiliated hijackers flew two Boeing 767 jets into the North and South Towers within minutes of each other; two hours later, both had collapsed . The attacks killed 2,606 people in and within the vicinity of the towers, as well as all 157 on board the two aircraft . Falling debris from the towers, combined with fires that the debris initiated in several surrounding buildings, led to the partial or complete collapse of all the buildings in the complex and caused catastrophic damage to ten other large structures in the surrounding area . </P> <P> The cleanup and recovery process at the World Trade Center site took eight months, during which the remains of the other buildings were demolished . The World Trade Center complex was rebuilt over more than a decade . The site is being rebuilt with six new skyscrapers, while a memorial to those killed in the attacks and a new rapid transit hub have both opened . One World Trade Center, the tallest building in the United States, is the lead building for the new complex, reaching more than 100 stories upon completion in November 2014 . </P> <P> The western portion of the World Trade Center site was originally under the Hudson River, with the shoreline in the vicinity of Greenwich Street . It was on this shoreline close to the intersection of Greenwich and the former Dey Street that Dutch explorer Adriaen Block's ship, the Tyger, burned to the waterline in November 1613, stranding Block and his crew and forcing them to overwinter on the island . They built the first European settlement in Manhattan . The remains of the ship were buried under landfill when the shoreline was extended starting in 1797, and were discovered during excavation work in 1916 . The remains of a second ship from the eighteenth century were discovered in 2010 during excavation work at the site . The ship, believed to be a Hudson River sloop, was found just south of where the Twin Towers used to stand, about 20 feet below the surface . </P>

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