George Bush

NEW YORK, NEW YORK - SEPTEMBER 11: Family, friends and colleagues of those killed in the 9/11 and the 1993 bombing terror attacks participate in the annual commemoration ceremony at the National 9/11 Memorial and Museum on September 11, 2021 in New York City. The nation is marking the 20th anniversary of the terror attacks of September 11, 2001, when the terrorist group al-Qaeda flew hijacked airplanes into the World Trade Center, Shanksville, PA and the Pentagon, killing nearly 3,000 people. (Photo by Chip Somodevilla/Getty Images)

Thousands gather to honor lives lost on 9/11

Thousands came together in New York City and across the nation as the U.S. paid tribute to those who lost their lives on Sept. 11, 2001. Ceremonies were held all across New York City, Shanksville, Pennsylvania and at the Pentagon as the nation vows to never forget 9/11.

New York police and firefighters hold a US flag as a band plays the US National Anthem at the National 9/11 Memorial during a ceremony commemorating the 20th anniversary of the 9/11 attacks on the World Trade Center, in New York, on September 11, 2021. (Photo by ED JONES/POOL/AFP via Getty Images)

Remembering events of 9/11, 20 years later

On the morning of September 11, 2001, the Twin Towers stood high among the New York City skyline as no one predicted the tragedy that would strike the buildings just hours later. At 7:59 a.m., American Airlines Flight 11 departed Logan International Airport in Boston and headed for Los Angeles, California.