This year, as we mark that unforgettable day that shook our lives, crushed our hearts and forever scorched the soul of this nation, we look back. We look back to honor those whose lives were taken and to strengthen our resolve as a nation to never let something like that happen again. Here are the haunting facts, by the numbers.
2: Planes flew into the World Trade Center in New York in the attack orchestrated by al-Qaida leader Osama bin Laden.
4: Planes were hijacked by terrorists.
14: Years ago it happened.
19: Terrorists hijacked the planes.
23: NYPD officers were killed.
40: People died near Shanksville, Pennsylvania, when one plane crashed there.
115: Nations had citizens killed in the attacks.
184: People were killed at the Pentagon in Washington, D.C., when one of the planes struck there.
343: Firefighters and paramedics were killed.
2,753: People were killed in New York when the twin towers were hit.
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2,977: Innocent people were killed in all.
3,051: Children are estimated to have lost a parent in the attacks.
1.8 million: Tons of debris was removed in New York after the attacks.
3.1 million: Hours of labor were required to clean up the debris at ground zero.
20 million: People have visited the Sept. 11 memorial in New York since it opened in 2011.
600 million: Estimated dollars were required for the cleanup.
Infinite: The heartache and mourning that resulted from that fateful day.