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12 defining photos we will never forget from 9/11

On the 20th anniversary of 9/11, these are some of the enduring scenes of a day of horror and heroism, sadness and shock, that no American will ever forget.
/ Source: TODAY

It's a day whose surreal images remain unforgettable.

Everyone remembers where they were at the time of the terrorist attacks on Sept. 11, 2001, when they first witnessed the scenes of horror and heroism, shock and sadness.

From the moment the first hijacked plane hit the north tower of the World Trade Center in New York City at 8:46 a.m. EST, a day seared into the country's collective memory delivered scenes unlike any ever seen on American soil.

Seventeen minutes later, the second plane hit the south tower before both 110-story towers ultimately collapsed. The apocalyptic sight in New York City was followed by the scene in Washington, D.C., where a plane flew into the Pentagon, and an open field near Shanksville, Pennsylvania, where a heroic group of passengers diverted United Airlines Flight 93 before the crash took their lives.

As the nation marks the 20th anniversary of the attacks on Saturday and mourns the 2,977 lives lost, here are the photos that captured that moment in time and the ensuing years of marking the tragedy — moments we can never forget.

Warning: Some of the images below could be disturbing.

Pedestrians run for cover after the collapse of the south tower.
Pedestrians run for cover after the collapse of the south tower.Suzanne Plunkett / AP
Bank of America employee Marcy Borders, who died at 42 in 2015 from cancer, is shown covered in dust as she takes refuge in an office building after one of the towers collapsed.
Bank of America employee Marcy Borders, who died at 42 in 2015 from cancer, is shown covered in dust as she takes refuge in an office building after one of the towers collapsed.Stan Honda / AFP
Attack on New York City
An unidentified New York City firefighter walks away from Ground Zero after the collapse of the Twin Towers. Anthony Correia / Getty Images
9/11 Missing Posters
September 11th missing person posters are shown still attached to a wall outside Saint Vincent's Hospital on Aug. 22, 2002, in New York City. Mario Tama / Getty Images
Funeral for New York Firefighter Lt. Dennis Mojica
Firefighters stand atop a fire engine with the flag draped casket of fellow fireman Lt. Dennis Mojica on Sept. 21, 2001, during a funeral service at St. Patrick's Cathedral in New York City.Joe Raedle / Getty Images
September 11 Retrospective
Former President George W. Bush holds an American flag during a Memorial Service at the Pentagon on Oct. 11, 2001. Mark Wilson / Getty Images
Missing Rescue Workers
Pedestrians near Ground Zero view photos of police and fire personnel missing since the attacks. Mario Tama / Getty Images
TOPSHOT-US-ATTACKS-ANNIV-ED FINE
Businessman Edward Fine covers his mouth as he walks through the debris after the collapse of one of the World Trade Center Towers in New York. Fine was on the 78th floor of 1 World Trade Center when it was hit by a hijacked plane. Stan Honda / AFP via Getty Images
First Firefighter Funeral After WTC Disaster
Firefighter Tony James cries while attending the funeral service for New York Fire Department Chaplain Rev. Mychal Judge on Sept. 15, 2001, in New York City.Joe Raedle / Getty Images
Five Years Later, New York Remembers 9/11 Attacks
Patricia Smith, the daughter of police officer Moira Smith, who was killed on 9/11, holds the hand of her father James Smith on stage during the reading of names of victims of 9/11 during ceremonies at Ground Zero on Sept. 11, 2006. Spencer Platt / Getty Images
Tribute in Light in New York City
The annual Tribute in Light is illuminated on the skyline of lower Manhattan behind the Statue of Liberty on the eve of the 18th anniversary of the 9/11 attacks on Sept. 10, 2019. Gary Hershorn / Getty Images
An American flag is unfurled at sunrise at the Pentagon on Sept, 11, 2020 to honor the 184 people killed in the 2001 terrorist attack.
An American flag is unfurled at sunrise at the Pentagon on Sept, 11, 2020 to honor the 184 people killed in the 2001 terrorist attack.Patrick Semansky / AP

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