An airplane is flying towards one of the Twin Towers while black smoke billows out the other tower.

Hijacked Flight 175 approaching the World Trade Center. Photo by Kelly Guenther.

Events of the Day

What happened on the morning of September 11, 2001?

On September 11, 2001, nineteen terrorists associated with al-Qaeda, an Islamist extremist group, hijacked four commercial airplanes scheduled to fly from the East Coast to California. In a coordinated attack that turned the planes into weapons, the terrorists intentionally flew two of the planes into the Twin Towers of the World Trade Center, a global business complex in New York City, causing the towers to collapse. They also flew a third plane into the Pentagon, the headquarters of the U.S. Department of Defense, in Arlington, Virginia. Passengers and crew members on the fourth plane launched a counterattack, forcing the hijacker pilot—who was flying the airplane toward Washington, D.C.—to crash the plane into a field in Somerset County, Pennsylvania, near the town of Shanksville.

The 9/11 attacks killed 2,977 people. This was the single largest loss of life resulting from a foreign attack on American soil. The attacks caused the deaths of 441 first responders, the greatest loss of emergency responders on a single day in American history.

Primary Sources

These primary resources include speeches, executive orders, legislative acts and debates, and government reports. 

Suggested Reading List

Fireboat: The Heroic Adventures of the John J. Harvey

Maira Kalman. Puffin Books, 2005.

(Preschool–Grade 3)

The Man in the Red Bandanna

Honor Crowther Fagan (author) & John Crowther (illustrator). CreateSpace Independent Publishing Platform, 2013.

(Grades 2–3)

Immigrant, American, Survivor: A Little Boy Who Grew Up To Be All Three

William Jimeno (author), Charles Ricciardi (illustrator). Charles Ricciardi, 2021.

(Grades 3–6)

America Is Under Attack: September 11, 2001: The Day the Towers Fell

Don Brown. Squash Fish, 2014.

(Grades 1–5)

Nine, Ten: A September 11 Story

Nora Raleigh Baskin. 2011, Atheneum Books for Young Readers

(Grades 3–7)

National Geographic Readers: September 11

National Geographic Kids. 2021.

(Kindergarten–Grade 3)

The 9/11 Report: A Graphic Adaptation

Sid Jacobson and Ernie Colon. Hill and Wang, 2006.

The Red Bandanna: A Life, A Choice, A Legacy

Tom Rinaldi. Penguin Press, 2016.

Out of the Blue: A Narrative of September 11, 2001

Richard Bernstein. New York: Times Books, 2002.

Firefight: Inside the Battle to Save the Pentagon on 9/11

Patrick Creed and Rick Newman. Presidio Press, 2008.

102 Minutes: The Untold Story of the Flight to Survive Inside the Twin Towers

Jim Dwyer and Kevin Flynn. New York: Times Books, 2004.

Among the Heroes: United Flight 93 and the Passengers and Crew Who Fought Back

Jere Longman. Harper Perennial, 2003.

The 9/11 Commission Report

National Commission on Terrorist Attacks Upon the United States. WW Norton: 2004.

Running toward Danger: Stories Behind the Breaking News of 9/11 

The Newseum. Rowman & Littlefield Publishers, Inc, 2002. Select sections

The Only Plane in the Sky

Garrett Graff. Simon & Schuster, 2019.

Pentagon 9/11

Alfred Goldberg. Historical Office, Office of the Secretary of Defense, 2007.

Related Resources

These related resources include lesson planspast public programs, and feature galleries on Inside the Collection.