The National September 11 Memorial and Museum is marking the 10th anniversary of the end of cleanup operations at the site with a tribute to recovery workers and first responders.
The event is scheduled for Wednesday evening at the Sept. 11 memorial plaza at the World Trade Center site. Former and current leaders will be present to express their thanks.
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 an estimated 1.8 million tons of steel and concrete.
Currently, 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 over 1,250 feet high.
The 9/11 memorial opened to the public in September. There's no completion date 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.