NYC: Ground Zero
Debris from the fallen towers after the September 11th attacks smoldered for more than five months. It resisted attempts by firefighters to extinguish the burning until most of the debris was removed.
The "Pile" is the name used by the site rescue, recovery and removal workers to describe the debris. The workers avoided using the name "Ground Zero" which describes the exact location on the ground where any explosion occurs, but became synonymous with the site nonetheless.
The site was officially cleared in May 2002, about four months earlier than expected. The "Pile" name hasn't been used since then. The "last-piece" of site structural steel, part of the 2 World Trade Center, was ceremoniously draped with the U.S. flag and carried out on the last day of the removal. It was symbolic of those people whose remains were never recovered or identified. It has since been recycled as the bow of the new San Antonio-class amphibious assault ship USS New York.
The remaining 181,400 tons of steel were sold for $120 a ton to foundries in China, India and South Korea, and later recycled as various things including automobile parts, challenge coins, commemorative coins, commemorative crucifixes and Stars of David, commemorative knives, food cans, household appliances, paper clips and rebar.