Eight years before 9/11, terrorists carried out their first attack on the World Trade Center, detonating a bomb beneath the Twin Towers.

On February 26, 1993, four terrorists rented a truck, filled it with explosives, drove it into the basement of the World Trade Center and blew it up in an attempt to bring down both towers. The buildings were heavily damaged by smoke and tenants had to leave for several weeks, but eagerly moved back in as soon as they were allowed. After this attack, the Port Authority of NY & NJ made a number of physical improvements to the building and changes in emergency protocol that helped save lives on 9/11.