Here we see an escalator being hoisted to the 101st floor of World Trade Center 1. (How did you think they got escalators up that high?) At first glance, the dizzying perspective of this photo will make your brain hurt.
More » 
Source: http://feeds.gawker.com/~r/gizmodo/full/~3/Fl8pc0vEQhQ/how-to-install-an-escalator-on-the-101st-floor-of-americas-tallest-building
MENTOR GRAPHICS IMS HEALTH IMATION IKON OFFICE SOLUTIONS
