Twenty years after the Sept. 11, 2001, terror attacks on the United States, families and loved ones gathered at memorial sites across the U.S. to honor the nearly 3,000 lives lost in the attack.

What You Need To Know

  • Millions of people gathered across the U.S. on Saturday to honor the lives of nearly 3,000 people who died in the Sept. 11, 2001, terror attacks

  • The ceremony at the World Trade Center memorial lasted roughly four hours, as family members recited the names of victims and at times, stopped to tearfully remember their legacies

  • “Twenty years feels like an eternity, but yet it still feels like yesterday,” said Lisa Reina, whose husband, Joseph Reina Jr., was killed in the North Tower when she was nine months pregnant

  • At the Pennsylvania site, where passengers and crew attempted to retake the plane from the hijackers, former President George W. Bush echoed Biden’s theme of unity, telling attendees that Sept. 11 showed Americans can come together despite their differences

The day’s proceedings began with a ceremony at the National 9/11 Memorial plaza in Lower Manhattan, where family members read aloud the names of those killed.

The careful, somber procession lasted roughly four hours, and stopped for six moments of silence – acknowledging the time when each of the World Trade Centers was struck and fell, as well as the times corresponding to the attack on the Pentagon and the crash of United Flight 93 in Shanksville, Pa.

The first moment of silence came at 8:46 am, when American Airlines Flight 11 struck the World Trade Center’s North Tower. The second came 17 minutes later, when the South Tower was struck at 9:03 am.

For many Americans, 9:03 am was the moment they realized America was under attack.

“It felt like an evil specter had descended on our world, but it was also a time when many people acted above and beyond the ordinary,” said Mike Low, whose daughter, Sara Low, was a flight attendant on American Airlines Flight 11.

Speaking at the beginning of Saturday’s memorial, Low described the “unbearable sorrow and disbelief” his family has shouldered in the two decades since her death.

But “as we carry these 20 years forward, I find sustenance in a continuing appreciation for all of those who rose to be more than ordinary people,” Low said.

Some of the speakers were not yet alive on Sept. 11, 2001 – a stark reminder of just how much time has passed. Instead, they spoke about the legacies their loved ones left behind.

At other times, the grief was fresh and piercing, with family members holding back sobs as they mourned the years lost. “Twenty years feels like an eternity, but yet it still feels like yesterday,” said Lisa Reina, whose husband, Joseph Reina Jr., was killed in the North Tower. She had been nine months pregnant with their son at the time.

Twenty years later, she spoke to her late husband through tears: “Our son is a spitting image of you,” she said. “He lights up my world every day. I see you and everything that he does, and I know that you see us, because I feel you. ... Until we meet again, my love, rest in peace.”

President Biden was joined at the New York ceremony by former Presidents Barack Obama and Bill Clinton.

Biden, who was scheduled to travel Saturday to all three memorials, stood solemnly for much of the ceremony, head bowed. At times, he was seen wiping away tears.

The president opted not to speak at the ceremonies Saturday; instead, he released a taped address the previous night that emphasized “heroism everywhere – in places expected and unexpected,” that emerged in wake of the 9/11 attacks.

“To me, that’s the central lesson of September 11,” Biden said. “Unity is our greatest strength.”

Later, Biden traveled to the site of the United Flight 93 crash near Shanksville, Pa., where he participated in a wreath-laying ceremony.

U.S. Defense Secretary Lloyd Austin and Chairman of the Joint Chiefs of Staff Army Gen. Mark Milley led the memorial service at the Pentagon Saturday morning, where they honored the lives of “fallen teammates” and vowed to uphold their values.

"We still work here,” Austin said. “We still remember. And we still uphold our values here: clear heads and fearless hearts.”

“The people who were lost that day are not just names and numbers,” Gen. Milley said. “They were irreplaceable to their family, instrumental in their jobs, women into the fabric of their community.”

At the Pennsylvania site, where passengers and crew attempted to retake the plane from the hijackers, former President George W. Bush echoed Biden’s theme of unity, telling attendees that Sept. 11 showed Americans can come together despite their differences.

“So much of our politics has become a naked appeal to anger, fear and resentment,” said the president who was in office on 9/11. “On America’s day of trial and grief, I saw millions of people instinctively grab their neighbor’s hand and rally to the cause of one another. That is the America know.”

Bush also gave a powerful tribute to the victims of United Flight 93.

“Twenty years ago, terrorists chose a random group of Americans on a routine flight to be collateral damage in a spectacular act of terror,” Bush said. “The passengers and crew of Flight 93 could have been any group of citizens selected by fate. ... The terrorists soon discovered that a random group of Americans is an exceptional group of people."

"Facing an impossible circumstance, they comforted their loved ones by phone, braced each other for action, and defeated designs of evil,” Bush continued. “These Americans were brave, strong, and united in ways that shocked the terrorists. It should not surprise any of us: this is the nation we know.”