Many who saw it all unfold remember those who were lost, and offer thanks to the heroes who stepped up in the face of tragedy.
As CBS2's Christina Fan reports, columns of light reach miles into the sky, reminding all of us on the ground of the emotions that linger, 20 years later.
"You know, 20 years later, you go on with your life, right? You live your life. But then, in this moment, you can't help but think back to that day," said Lisa Bruckenstein.
"You remember that day, and just seeing all the pictures of everybody going 'Have you seen this person?' And it just broke your heart," one person said.
At Liberty State Park, some came to reflect, and to remember close friends and loved ones who perished.
Complete Coverage: 9/11 Twenty Years Later
"We got into the city by ferry. And we had seen that the top of the building was on fire," said Middletown resident Jennifer Fontana.
Fontana and Jacqueline Lobello worked at Cantor Fitzgerald, in the North Tower. They were going to work later than usual on September 11th. It saved their lives.
"And I see the people who've perished, and they were so young. And as we're getting older, so grateful to still be here, and of course feel guilty that they're not," Fontana said.
"We lost a lot of friends. her best friend, Monica Goldstein, we lost her. So we're here to pay our respect to all our friends and our co-workers, and everybody else, all the innocent lives that were taken that day. And we're lucky that we're still here," Lobello said.
Friday, the fleet of heroes who carried out the largest water evacuation in history was honored. Water cannons were used to pay tribute to the mariners who answered the call, rescuing more than 500,000 people were trapped in Lower Manhattan, taking them safely across the harbor.
CBS2's Christina Fan contributed to this report.
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