A fire-damaged chair lies inside an office on the fourth floor of the Pentagon. A fire-damaged chair lies inside an office on the fourth floor of the Pentagon on Sept. 14, 2001. Damage to the Pentagon was caused when the hijacked American Airlines flight slammed into the building on Sept. 11th. The terrorist attack caused extensive damage to the west face of the building and followed similar attacks on the twin towers of the World Trade Center in New York City. SHARE: Download: Full Size (0.06 MB) Credit: VIRIN: 694868-E-MFK53-814.jpg Photo Gallery