Examples of buildings which did not collapse from fire:

In February 2005 the 32-story Windsor Building in Madrid, Spain, caught fire and burned for two days. The building was completely engulfed in flames at one point. Several top floors collapsed onto lower ones, yet the building remained standing. 

In October 2004 in Caracas, Venezuela, a fire in a 56-story office tower burned for more 17 hours and spread over 26 floors. Two floors collapsed, but the underlying floors did not, and the building remained standing. 

In February 1991 a fire gutted eight floors of the 38-story One Meridian Plaza building in Philadelphia, Pennsylvania. The fire burned for 18 hours. The building did not collapse.

  In February 2005 there was another "towering inferno" in Taiwan. The fire burned for about an hour and a half, but the building never came close to collapsing. 

So we have a fire burn for 56 minutes and collapse WTC1.. simply amazing. Even when It was rated to withstand multiple Boeing 707 Collisions at 600mph