NEW YORK – Americans gather Sunday to pray at cathedrals in their greatest cities and to lay roses before fire stations in their smallest towns, remembering the worst terrorist attacks on U.S. soil.
Around the world, many others will do something similar because so much changed for them on that day, too.
Ten years has arrived since 3,000 were killed at the hands of a global terror network when terrorists crashed hijacked planes into the World Trade Center and the Pentagon, and a fourth plane crashed into a field in rural western Pennsylvania.
On Sunday, bells will toll. Americans will see new memorials in lower Manhattan, rural Pennsylvania and elsewhere, symbols of a resolve to remember and rebuild.
But much of the weight of this year's ceremonies lies in what will largely go unspoken. There's the anniversary's role in prompting Americans to consider how the attacks affected them and the larger world and the continuing struggle to understand 9/11's place in the lore of the nation.
"A lot's going on in the background," said Ken Foote, author of "Shadowed Ground: America's Landscapes of Violence and Tragedy," examining the role that veneration of sites of death and disaster plays in modern life. "These anniversaries are particularly critical in figuring out what story to tell, in figuring out what this all means. It forces people to figure out what happened to us."
On Saturday in rural western Pennsylvania, more than 4,000 people began to tell the story again.
At the dedication of the Flight 93 National Memorial near the town of Shanksville, former Presidents George W. Bush and Bill Clinton and Vice President Joe Biden joined the families of the 40 passengers and crew aboard the jet who fought back against their hijackers.
"The moment America's democracy was under attack our citizens defied their captors by holding a vote," Bush said. Their choice cost them their lives.
The passengers and crew gave "the entire country an incalculable gift: They saved the Capitol from attack," an untold amount of lives and denied al-Qaida the symbolic victory of "smashing the center of American government," Clinton said.
They were "ordinary people given no time at all to decide and they did the right thing," he said.
"And 2,500 years from now, I hope and pray to God that people will still remember this."
The Pennsylvania memorial park is years from completion. But the dedication and a service to mark the 10th anniversary of the attacks are critical milestones, said Sally Ware, one of the volunteer "ambassadors" who has worked as a guide at the site since the disaster.
Ware, whose home was rocked when the jet crashed two miles away, recalled how hundreds of people flocked to the site in the days afterward to leave their own mementos and memorials. She began volunteering after finding one along the roadside -- a red rose placed atop a flight attendant's uniform.
"It really bothered me. I thought someone has to take care of this," said Ware, whose daughter is a flight attendant.
Now, a decade later, she said the memorial may do little to ease the grief of the families of those who died in the crash.
But the weekend's ceremonies recall a story with far broader reach. The ceremonies honor those who "fought the first battle against terrorism -- and they won," Ware said. "It's something I don't want to miss. It's become a part of my life."
On Sunday, the focus turns to ceremonies at the Pentagon, just outside Washington, D.C., and in lower Manhattan for the dedication of the national Sept. 11 memorial. President Barack Obama planned to attend events at the sites and was to speak at a Sunday evening service at the Kennedy Center.
The New York ceremony begins at 8:30 a.m., with a moment of silence 16 minutes later -- coinciding with the exact time when the first tower of the trade center was struck by a hijacked jet.
And then, one by one, the reading of the names of the 2,977 killed on Sept. 11 -- in New York, at the Pentagon and in rural Pennsylvania.
And so arrives a Sunday dedicated to remembrance, with hundreds of ceremonies across the country and around the globe -- from a memorial Mass at St. Patrick's Cathedral in New York to a ceremony featuring nine-stories-tall replicas of the twin towers on a plaza in Paris.