The 9/11 attacks happened on September 11, 2001. On that day, the attacks occurred in a detailed timeline beginning early in the morning around 7:59 a.m. when American Airlines Flight 11 took off. Key moments include:

• At 8:46 a.m., Flight 11 crashed into the North Tower of the World Trade Center in New York City.
• At 9:03 a.m., United Airlines Flight 175 crashed into the South Tower of the World Trade Center.
• Around 9:37 a.m., American Airlines Flight 77 crashed into the Pentagon.
• At about 10:03 a.m., United Airlines Flight 93 crashed in Pennsylvania after passengers attempted to regain control.
• The South Tower collapsed at 9:59 a.m., and the North Tower collapsed at 10:28 a.m. later in the morning.

This day became a defining moment in modern history, marking a major terrorist attack on the United States.