The September 11 attacks took place in Manhattan, New York City.
Manhattan ( [ mænˈhætən ] , [ mənˈhætən ] ) is the most densely populated borough of New York City , its economic and administrative center , and the city 's historical birthplace . September 11 attacks . Two of the planes , American Airlines Flight 11 and United Airlines Flight 175 , were crashed into the North and South towers , respectively , of the World Trade Center complex in New York City .