Mayor Michael Bloomberg, former Mayor Rudolph Giuliani and former Gov. George Pataki attended the evening event at the Sept. 11 memorial plaza at the World Trade Center site.
"It looks peaceful, the extreme opposite of what I saw when I first came down," said Jaye Markwell, a Connecticut volunteer with the Salvation Army who helped deliver food during the effort.
After the attacks, an army of workers spent months cleaning up the site. The formal end of that operation was May 30, 2002, and was marked with the removal of the last column of steel that had still been standing.
In that ceremony, the steel column was covered in a black shroud and taken away, along with an empty stretcher covered with an American flag.
Those at the site worked days and nights to clear away the enormous pile of rubble left behind after the towers fell. They removed about 1.8 million tons of steel and concrete.
"It's nice to be down here among people who really put their heart into it," said Michelle Tennant-Timmons, an event producer from Harlem who volunteered at a relief center 10 years ago.
The One World Trade Center building replacing the twin towers is under construction, with workers recently erecting steel columns that took its unfinished skeleton to more than 1,250 feet high.
The 9/11 memorial opened to the public in September. No completion date has been set for the museum, as construction has largely stopped over a financial dispute between the Port Authority of New York and New Jersey, which owns the site, and the foundation that controls the memorial and museum.
Get Eyewitness News Delivered