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 charges 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."
As happens annually, family members of those killed in the attacks gathered Thursday morning to read the names of the deceased, pausing the sad roll call only four times: when the first plane struck the World Trade Center, when the second plane struck, when the first tower fell and when the second tower fell.
The memorial plaza was closed to the public for most of the day and only available to family members. It will reopen at 6 p.m., and thousands of New Yorkers are expected to mark the anniversary at the twin reflecting pools where the towers once stood.
On the same day 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.
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"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.
—By The Associated Press with CNBC.com