The solemn observation at the Oklahoma City National Memorial began at 9:02 a.m., the minute the Alfred P. Murrah Federal Building was destroyed by a fuel oil and fertilizer bomb on April 19, 1995.
They observed 168 seconds of silence, one second for each of those who died, before the victims' children began reading the names.
"These children, like all of you and our city, are portraits of our survival," said Frank Hill, chairman of the foundation that supports the memorial, which is built on the site where the Murrah building once stood.
"Thousands come to this memorial every week to find peace, hope and serenity," he said Monday.
After the reading of names, many of the several hundred people gathered for the anniversary walked to the memorial's field of chairs, where each empty chair symbolizes a person lost.
Jason Smith, 31, of Oklahoma City, read names including that of his mother, Linda McKinney.
"To be able to come down and be able to read my mom's name along with the rest of the victims is a tremendous honor," he said. "Even though it's been nine years and a lot of us have moved on in our lives and grown, it's nice to take a step back and remember that fateful day and honor their memory."
Also in attendance were family members of victims of the Sept. 11 terrorist attacks. Some have forged a bond with those who lost loved ones in Oklahoma City.
"They're ahead of us on the path and they've kind of been pulling us along," said Barbara Salvadore, whose brother, firefighter Lt. Peter Freund, died in the World Trade Center. "They know how we feel."
A new exhibit at the memorial's museum displays 23 pieces of art that were in the Murrah building at the time of the blast. Nine other pieces of artwork did not survive the explosion.
Longtime arts champion Joan Mondale, wife of former vice president Walter Mondale, had dedicated art in the building in 1978. She returned to look at the new exhibit Monday.
"Today we rejoice in celebrating these surviving works of art, which like the survivors in this audience, remind us that beauty and courage will prevail," she said.
Meanwhile, trial continued in McAlester for bombing conspirator Terry Nichols.
On Monday, Nichols' lawyers cross-examined an FBI agent who interviewed Nichols two days after the bombing.
Agent Steve Smith said Nichols was very careful about how he answered questions and was reluctant to talk to agents. Smith said Nichols told agents he didn't think he did anything wrong, but that — quote — "lawyers can turn things around."
Smith also testified Nichols had said he thought executed bomber Timothy McVeigh might have been involved in the bombing, but couldn't see why McVeigh would do it.
Nichols, 49, is serving a life sentence on federal convictions for his role in the bombing. He was convicted of conspiracy and involuntary manslaughter for the deaths of eight federal law enforcement officers.
Nichols is on trial for 161 counts of first-degree murder for the deaths of the other 160 victims and one victim's fetus. Prosecutors are seeking the death penalty.
Before the start of testimony Monday, prosecutors said they expected to finish their case on May 3 or May 4, six weeks after they first began presenting evidence.
Nichols' attorney Brian Hermanson said the defense will begin presenting its case May 6.
Nichols was at home the day the bomb exploded. But prosecutors allege he helped McVeigh build the 4,000-pound ammonium-nitrate-and-fuel-oil bomb and pack it inside a Ryder truck.
McVeigh was convicted on federal bombing charges and was executed in 2001.