1. Home

Discuss in my forum

9-11 Photos: Attack on the World Trade Center

By

8 of 10

Seven Hours Later: WTC Building 7 Collapses
Seven hours after the World Trade Center twin towers fell, the 47-story WTC building 7 collapsed

Seven hours after the World Trade Center twin towers fell, the 47-story WTC building 7 collapsed

Photo © Pool / Getty Images
Flying debris and raging fire from the collapsed World Trade Center towers had an impact on nearby buildings. Seven hours after the Twin Towers fell, the 47-story WTC building 7 collapsed.

After years of investigations, the National Institute of Standards and Technology (NIST) found that the intense heat on the floor beams and girders weakened a critical support column in WTC Building 7. More: Fires Fell World Trade Center Building 7

Learn More About September 11, 2001:

NEXT: Searching through the World Trade Center Wreckage >>

  1. About.com
  2. Home
  3. Architecture
  4. Great Buildings
  5. World Trade Center
  6. WTC Building 7 Collapses -- Severely Damaged from Terrorist Attacks on Twin Towers

©2014 About.com. All rights reserved.