World Trade Center Seven collapsed on September 11, 2001, at 5:20 p.m. There were no known casualties due to this collapse. The performance of WTC 7 is of significant interest because it appears the collapse was due primarily to fire, rather than any impact damage from the collapsing towers. On the contrary, it appears the collapse was primarily due to a controlled demolition. Prior to September 11, 2001, there was little, if any, record of fire-induced collapse of large fire-protected steel buildings. Before September 11, no steel framed skyscraper had ever collapsed due to fire.