For the first time since the Sept. 11, 2001, attacks, victims' families gathered to mark the anniversary not where the World Trade Center's twin towers once stood, but at a nearby gray stone plaza.

Fewer mourners gathered to pay tribute to lost loved ones and hear the victims' names read out than last year, according to a city estimate. Unlike the pristine weather the day of the attack, it rained Tuesday.

"It was very different being at the park today instead of here," said Charlene Morgen, whose cousin Debora Maldonado was killed in the attack. "The crowd was smaller, it rained for the first time — it was almost like saying goodbye, this is the end."

First responders, volunteers and firefighters who helped rescue New Yorkers from the collapsing twin towers read the names of the city's 2,750 victims — a list that grew by one with the addition of a woman who died of lung disease in 2002. Several first responders referred to the illnesses and deaths of their colleagues that they blame on exposure to toxic dust.

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"I want to acknowledge those lost post-9/11 as a result of answering the call, including police officer NYPD James Zadroga," said volunteer ambulance worker Reggie Cervantes-Miller. Zadroga, 34, died over a year ago of respiratory illness after spending hundreds of hours working to clean up Ground Zero.

Victims' spouses, children, siblings and parents had read names before, often breaking down with heartrending messages to their loved ones, blowing kisses to the sky. At Zuccotti Park, where the sounds of trucks and buses sometimes overwhelmed speakers, fewer tears were shed and most readers didn't speak at length — even when mentioning siblings or children who had been killed.

Around the country, Americans went through the all-too-familiar day of remembrance and grief as they looked back on that day six years ago when terrorists hijacked four jetliners and killed nearly 3,000 people at the trade center, the Pentagon and a Shanksville, Pa., field.

President Bush attended somber ceremonies at the White House and the spot where terrorists flew a plane into the Pentagon. Surviving family members and volunteers read the names of the 40 victims of the Pennsylvania plane crash at a temporary memorial near where the plane went down.

In Manhattan, victims' families said the ceremony in the park did not evoke the same emotions.

"I guess they mean well, but I really wasn't happy," said Sal Romagnolo, whose son, Joseph Romagnolo, worked in the trade center. "I get nothing out of this park."

Hundreds streamed out of the ceremony after about an hour and fewer than 60 remained at the end. The city estimated 3,500 family members and mourners turned out, down from 4,700 attendees at the fifth anniversary.

The city moved the ceremony because of construction at the site, where several idle cranes overlooked a partially built transit hub, planned 1,776-foot office tower and Sept. 11 memorial.

Some victims' relatives had threatened to boycott the ceremony and hold their own remembrance if they were not granted access to Ground Zero. The city and the Port Authority of New York and New Jersey — which owns the trade center site — allowed relatives to descend a ramp to lay flowers inside a reflecting pool with two 6-foot outlines of the towers inside, and touch the ground where the trade center once stood.

Howard Gabler, who worked on the 47th floor of the trade center's north tower and escaped on the day of the attack, came to mourn his son, Fredric, who worked on the 104th floor of the same tower. He has no remains of his son.

"This is where he died and we have nothing else," Gabler said. "It's very painful, it's very painful all the time, but today was, I guess, worse knowing we're not going to be back down there.

Gabler said he touched the ground, which he fears will not be available to him next year as construction goes on. "So today I kissed my hand and I kissed the ground — I'm still kissing him."

Former Mayor Rudy Giuliani returned to Ground Zero Tuesday, despite objections by several victims' families and firefighters who said he shouldn't speak at the remembrance because he is running for president. Democratic presidential hopeful Hillary Rodham Clinton attended the ceremony, but did not speak.

Giuliani was greeted with a smattering of applause after his brief remarks, which followed the third of the traditional four moments of silence: one each to mark the times when the two planes hit the buildings, and two more for when each tower fell.

Mayor Michael Bloomberg, who has presided over each of the anniversary events, described Sept. 11, 2001, as "the day that tore across our history and our hearts. We come together again as New Yorkers and as Americans to share a loss that can't be measured."

As in past years, the city shone two blue beams of light up in the night sky at sundown.