Relatives and loved ones of 9/11 victims convened Sunday to mark the 15th anniversary of the terror attacks. The milestone anniversary ceremony that took place at Ground Zero featured some new music and readings this year.
But they kept traditions that have made the ceremony a constant in how America remembers Sept. 11, even as Ground Zero and the nation changes. The customs included moments of silence and tolling bells, an apolitical atmosphere and the reading of the nearly 3,000 names of those killed in New York, at the Pentagon and near Shanksville, Pennsylvania.
Some family members reciting the names of loved ones killed on 9/11 have spoken about how their losses have inspired them to do good for others.
Jerry D'Amadeo was 10 years old when he lost his father, Vincent Gerard D'Amadeo. He was the opening speaker. He said he worked this summer with children at Sandy Hook Elementary School in Newtown, Connecticut, where 26 children and adults were massacred in 2012.
He said, "Sometimes the bad things in our lives put us on the path to where we should be going."
Ryan Van Riper said he planned to honor his slain grandmother, Barbara Shaw, by serving the country.
Some are going into National September 11 Museum, which is open only to victims' families until Sunday afternoon, when the public will be allowed to enter. About an hour before the official commemoration start, police officers in uniform and bagpipers rehearsed part of the ceremony involving a display of the US flag.
President Barack Obama spoke at an observance at the Pentagon. Hundreds of people also attended at a ceremony at the Flight 93 National Memorial in Shanksville.
The presidential campaign took center stage, however, as Democratic candidate Hilary Clinton left early after apparently getting overheated. A video taken by a bystander shows Hillary Clinton wobbling and being held up by three people as she left a ceremony at the World Trade Center marking the 15th anniversary of the September 11 attacks.
Clinton's campaign says the Democratic presidential nominee left the ceremony in New York early after feeling "overheated."
The video showed her stumbling while getting into a van.
A few hours later, Clinton walked out of daughter Chelsea Clinton's apartment on her own, saying she was "feeling great."