Desde World Trade Center (1973–2001) - Wikipedia ...On February 13, 1975, a three-alarm fire broke out on the 11th floor of the North Tower. It spread to the 9th and 14th floors after igniting telephone cable insulation in a utility shaft that ran vertically between floors. Areas at the furthest extent of the fire were extinguished almost immediately; the original fire was put out in a few hours. ...