Keywords: May 28 2002 Ground Zero Cleanup 02.jpg New York City May 28 2002 -- Recovery works at New York City ™s Ground Zero sign the last remaining World Trade Center structure Column Number 1001B of Two World Trade Center The 30-foot column remained standing following the collapse of the twin towers when terrorists flew two commercial airliners into both skyscrapers on September 11 2001 The resulting collapse created a mountain of 1 8 million tons of steel and concrete More than 3000 people perished in the attack U S Navy photo by Photographer ™s Mate 2nd Class Bob Houlihan http //www news navy mil/view_single asp id 1652 PD-USGov-Military-Navy Ground Zero World Trade Center in 2002 May 2002 photographs |