9/11 victims remembered on 13th anniversary

NEW YORK -- Still-mourning family members again gathered at ground zero, as has become the grim annual tradition, to mark the 13th anniversary of the terror attacks that rocked the nation and changed the way we live our daily lives.

Under gray skies, moments of silence marked each significant moment of the day, with bells tolling on six separate occasions, to mark the moments each plane hit the towers, the Pentagon and a field in Shanksville, as well as when both towers fell.

Memorial organizers took over primary responsibility for the ceremony from the city for the first time, and they continued concentrating the event on victims' loved ones, even as the museum creates a new, broader framework for remembering 9/11.

At sundown, the Tribute in Light will again shine into the Lower Manhattan sky. The twin beams of light also honor those who worked so hard to get New York City through its greatest trial. The lights, which can be seen for miles, fade away at dawn Friday.

The crowds gathered to remember the mothers, fathers, sisters, brothers, aunts, uncles, sons, daughters, friends and colleagues who perished on this day 13 years ago, a time period that is singed in memories and for many feels like it just happened yesterday.

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At the ceremony on the 3-year-old memorial plaza at the site of the World Trade Center, relatives recited the names of the nearly 3,000 people who died, as well as the 1993 Trade Center bombing victims' names.

President Barack Obama paid tribute to the victims during a ceremony at the Pentagon.

"Thirteen years after small and hateful minds conspired to break us, America stands tall and America stands proud," the president said. "And guided by the values that sustain us, we will only grow stronger."

And around the world, thousands of volunteers pledged to do good deeds, honoring an anniversary that was designated a National Day of Service and Remembrance in 2009.

And while little about the annual ceremony at ground zero has changed, so much around it has.

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For the first time, the National September 11 Museum - which includes gut-wrenching artifacts and graphic photos of the attacks - is open on the anniversary. Fences around the memorial plaza have come down, integrating the sacred site more fully with the streets of Manhattan while completely opening it up to the public and camera-wielding tourists.

A new mayor is in office, Bill de Blasio, one far less linked to the attacks and their aftermath than his immediate predecessors. And finally, a nearly completed One World Trade Center has risen 1,776 feet above ground zero and will be filled with office workers by this date in 2015, another sign that a page in the city's history may be turning.

For some who lost loved ones in the attacks, the increasing feel of a return to normalcy in the area threatens to obscure the tragedy that took place there and interfere with their grief.

"Instead of a quiet place of reflection, it's where kids are running around," said Nancy Nee, whose firefighter brother, George Cain, was killed in the attacks. "Some people forget this is a cemetery. I would never go to the Holocaust museum and take a selfie."

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But for others, the changes are an important part of the healing process.

"When I first saw (One World Trade Center), it really made my heart sing," said Debra Burlingame, whose brother Charles Burlingame was the pilot of the plane that crashed into the Pentagon. "It does every time I see it because it's so symbolic of what the country went through."

"I want to see it bustling," she said. "I want to see more housing down there; I want to see it alive and bursting with businesses."

The memorial plaza will be closed to the public for most of the day and available only to family members. It will reopen at 6 p.m., at which point thousands of New Yorkers are expected to mark the anniversary at the twin reflecting pools where the towers once stood.

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In May, when the museum opened in a ceremony attended by President Barack Obama, the fences that had surrounded the plaza for years disappeared, as did the need for visitors to obtain a timed ticket. Now, thousands of people freely visit every day, from cellphone-toting travelers to workers on a lunch break, and those crowds will only swell further this year when One World Trade Center finally opens.

"The memorial and museum is extremely important to those impacted on 9/11," said Mary Fetchet, whose son died in the attacks. "And surrounding that memorial, lower Manhattan has been revitalized."

The first ceremony at the site was held six months after the Twin Towers fell and was organized by then-Mayor Michael Bloomberg and his aides. Bloomberg, who took office just three months after the attacks, remained in charge, acting as the master of ceremonies for the next decade.

After other elected officials attempted to gain a larger role at the solemn event, in 2012, all politicians - including Bloomberg - were prohibited from speaking at the event. That remains the case now, as de Blasio, who took office in January, agreed to let the National September 11 Memorial & Museum at the World Trade Center Foundation organize the commemoration ceremony. Bloomberg is the foundation's chairman.

The Associated Press contributed to this report.