http://aotearoaawiderperspective.wordpress.com/2012/02/16/bridgenorthcastle-or-why-two-planes-cannot-collapse-three-steel-framed-high-rises/
This is Bridgenorth Castle.

Bridgenorth castle was built by a very unsavoury character who took pleasure in gouging children’s eyes out with his fingers and killing people by starvation and torture and other general unpleasantness but I digress.
What, you ask, does Bridgeworth castle as suggested in the title of this post have to do with the collapse of the three WTC buildings on 911?
Let’s start with the size of the building. In order to get a sense of the size of the building (about 70 feet) I would like to draw your attention to the reverse triangle at the top of the wall. It is a rather thin line but that is the double roof which once topped the tower.
The tower was not the keep but a guard house and if you look at the right side of the building you see a narrow line from top to bottom which once held the iron portcullis. The row of holes in the wall from left to right held the beams from the floor and the total floors were approximately three. For more information here is the link to the time team doco on the building. Read more here