NEW YORK (CBSNewYork/AP) — With the solemn toll of a bell and a moment of silence, the nation paused Thursday to mark the 13th anniversary of the Sept. 11 terror attacks.

Family and friends of those who died read the names of the nearly 3,000 people killed in New York, at the Pentagon and near Shanksville, Pennsylvania.

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As the Honor Guard arrived, the only sound was the rush of water from the memorial pools where the towers stood until 13 years ago.

Gone were the musical ensembles, poems and speeches of years past, with the commemoration reduced to its essence – the tolling of bells to mark the significant moments along the painful timeline and the names of the dead.

The sad roll call paused six times: to mark the moments when the first plane struck the World Trade Center, when the second plane struck, when the first tower fell, when the second tower fell, when the third plane struck the Pentagon and when the fourth plane crashed in Pennsylvania.

Joanne Barbara, whose husband of 30 years Gerard Barbara, was a FDNY captain who died, urged all to feel for not only the lost but “those who continue to suffer from the aftermath.”

“May God bless America, and may we never, never forget,” she said.

As family members spoke, there were tears, of course, but there were smiles as well – and even a laughter in the form of a joke among sisters.

“I pay tribute to you by wearing your godawful green Converses today with the tacky yellow shoelaces,” one woman said. “I know somewhere you’re having a good laugh.”

A son also paid tribute to his mother.

“Your crazy spirit lives over us, Ma,” the man said.

More and more, there are people too young to remember the day clearly – becoming familiar with the annual ritual of grief. Two nephews spoke to lost uncles.

“I never got the chance to meet you, but you’ll always be in our heart,” one said.

“Even though I really didn’t know you, you will always be family in my heart and I will always love you,” another said. “And in your honor I have decided to serve our country with the United States Marine Corps.”

“Thirteen years ago, I was born on my grandmother’s birthday. She made my mom promise for us to share every birthday together,” one boy said. “We never had the chance to do that, but the gift of me being born on our birthdays is eternal.”

There was more serenity and seeming more acceptance, it seemed. But the pain never fully recedes.

“My only child, my beloved daughter,” a mourner said.

“Daddy we love you. We miss you,” another said.

“I know you would’ve loved to be with me in two weeks to see Jeter’s last game, but I’ll be there for the two of us,” a third said.

“I continue to mourn my fellow twin, my vanquished tower, my beloved baby brother,” a fourth said.

A widow spoke of the grandchildren her husband never met.

“My heart breaks that you are not here to enjoy them,” she said.

And as CBS 2’s Dave Carlin reported, the memorial remained full of people late into the night Thursday.

Under the stars and massive beams of light as the 9/11 Tribute in Light shown overhead, Frank Gotlibowski of Rocky Hill, Connecticut added to the row of flowers on the name of his friend, Jeffrey Donald Bittner, on the memorial.

Bittner was only 26 when he died in the South Tower.

“It’s very touching to me,” Gotlibowski said. “It’s great that the first time in 13 years that I’ve been able to visit the site on the day of the anniversary.”

Whether people had a personal connection or not, the horror of 9/11 was at the top of everyone’s mind.

“I was a little kid when it happened. I’m only 20 years old. But it’s still fresh – I go to school in the area, so it’s definitely, like, something that you think about every time I see the building,” said Justin Miller of Coney Island, Brooklyn.

Little about the annual ceremony at ground zero has changed. But so much around it has.

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.

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.

“Thirteen years later, it seems like yesterday,” said John Cartier, whose brother James’ motorcycle is on display at the National September 11 Museum. “With each passing day, it still hurts.”

“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.”

“When you see the skyline, I always saw the Twin Towers and now I just see one building,” one woman, who was on her way to a meeting at the World Trader Center on 9/11, told 1010 WINS’ Roger Stern. “For me, it’s not the same. The skyline is changed. It will never be the same again.”

Franklin Murray wore a shirt with a photo of his brother, Harry Glen, and the words “our angel” above the photo and “the wind beneath our wings” below. Glen worked at Cantor Fitzgerald, one of the companies most decimated.

He said he wanted to see the memorial for the first time, and it gave him a “funny feeling” to know there was now a memorial. He has come to the ceremony before but “before it was getting harder, so I forced myself to get down here.”

“Coming down to the area is rough,” he said.

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 is 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.

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.

One man, who lost his father on Sept. 11 and attends the anniversary ceremony every year, said the museum is moving.

“Very fact-based, done in a very tasteful way and sends the right message of, ‘We need to remember these people’ and it’s something that’s going to in our hearts for the rest of our life,” he told WCBS 880’s Sean Adams. “I’m impressed both with the memorial and the waterfalls as well as the museum.”

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.”

“Today, as we look around us, we see that lower Manhattan has come roaring back, becoming a hub not only for global finance, but our city’s most diverse and dynamic neighborhood,” said Assemblyman Sheldon Silver.

“We had to work hard to get the businesses back, to get the people back,” Rudy Guiliani, who was mayor during the attacks, told CBS 2’s Weijia Jiang. “A lot of people never wanted to return.”

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 Mayor Bill de Blasio 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.

Bloomberg attended the ceremony Thursday, along with Giuliani, de Blasio, New Jersey Gov. Chris Christie, New York Gov. Andrew Cuomo and others.

As part of the anniversary, the Tribute in Light has returned to lower Manhattan. The twin beams are a symbolic recreation of the Twin Towers.

For the first time, the public will be allowed to view the lights from the 9/11 memorial plaza, from 6 p.m. until midnight.

The Port Authority of New York and New Jersey also honored their fallen employees Thursday.

“To honor the memory of those 84 Port Authority employees who we lost 13 years ago today and their six colleagues that perished in 1993,” new chairman John Degnan said.

He said One World Trace Center and the construction around it is a testament to striking a balance between honoring the past and envisioning the future, WCBS 880’s Monica Miller reported.

“In this way, we will honor them in every task they undertake and their memories will inspire us each and every day,” he said.

Also Thursday, the president observed a moment of silence outside the White House with his wife Michelle and Vice President Joe Biden before heading to the Pentagon’s 9/11 memorial.

President Barack Obama (L), First Lady Michelle Obama and Vice President Joe Biden (R) stand for a moment of silence on the South Lawn of the White House in Washington, DC, September 11, 2014, marking the 13th anniversary of the 9/11 attacks on the United States. (credit: Jim Watson/AFP/Getty Images)

President Barack Obama (L), First Lady Michelle Obama and Vice President Joe Biden (R) stand for a moment of silence on the South Lawn of the White House in Washington, DC, September 11, 2014, marking the 13th anniversary of the 9/11 attacks on the United States. (credit: Jim Watson/AFP/Getty Images)

“Thirteen years after small and hateful minds conspired to break us, America stands tall and America stands proud,” Obama said.

Hundreds of family members, dignitaries and spectators also gathered at a ceremony in a field in Shanksville, Pennsylvania, where the United Airlines plane crashed on Sept. 11, 2001.

Flight 93 was traveling from Newark to San Francisco when al Qaeda-affiliated terrorists took control, with the likely goal of crashing it into the White House or Capitol.

The 9/11 Commission concluded the hijackers downed the plane in southwestern Pennsylvania as the 33 passengers and seven crew members revolted.

People gather during 13th anniversary ceremonies commemorating the September 11th attacks at the Wall of Names at the Flight 93 National Monument September 11, 2014 in Shanksville, Pennsylvania. (Photo by Jeff Swensen/Getty Images)

People gather during 13th anniversary ceremonies commemorating the September 11th attacks at the Wall of Names at the Flight 93 National Monument September 11, 2014 in Shanksville, Pennsylvania. (Photo by Jeff Swensen/Getty Images)

At the ceremony, the victims were posthumously awarded a Congressional Gold Medal, the nation’s highest civilian honor. The medal will be displayed temporarily at the memorial through Sunday, and will be part of a permanent exhibit once the visitors’ center opens, hopefully next year.

The same medals were being awarded at the Pentagon and World Trade Center sites.

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