Inside Twin Tower's Structure and the 911 Attack - Original World Trade Center

The Twin Towers, which official name were 1 World Trade Center and 2 World Trade Center, were the tallest in the world from 1971 - 1973. On September 11, 2001, the two buildings got attacked by 2 hijacked Boeing 767, and later collapsed. 2977 people were killed. That was a very tragic day for the United States of America.