NEW YORK (CBSNewYork) — On the eve of the 13th anniversary of the attacks of Sept. 11, 2001, people gathered at the 9/11 Museum to remember the horror and losses of that day.

As 1010 WINS’ Holli Haerr reported, Aaron Greenstein of the Port Authority of New York and New Jersey police was at the World Trade Center site on 9/11. He and his wife, Barbara, came to the museum Wednesday to see the history that he and his friends and co-workers were part of.

“I responded from the Lincoln Tunnel after the first plane crashed into the towers. I was under Building 5 when the first building came down,” Aaron Greenstein said. “I lost plenty of friends, relatives.”

“It’s a very emotional time. To this day, loud noises – basses in weddings – he’ll be outside. Once the floor starts shaking, he leaves,” Barbara Greenstein added.

Aaron Greenstein said coming to the scene is emotional, but he comes to remember the good times.

A man Phil from Staten Island came to the scene to honor and learn more about the final moments of people who were lost.

“My friend, Steven Olson, he passed away on 9/11. And his truck is there – he was in Ladder Company No. 3,” Phil said.

Another man named Daniel is retired from the Air Force, and he also lost a friend.

“He made it down to the 43rd floor, helping elderly people – you know, senior citizens – leave the building. That’s when the North Tower collapsed,” Daniel said. “His name was John Michael Griffin.”

Daniel said it is hard to come to ground zero, but important.

“Reflection and remembrance of my friend, and other people who died here,” he said.

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