The observation deck goes all the way around, with telescopes at each corner. The cage is sized so that only a sideshow rubber man could climb through.

There’s an old FM transmitter on top of the building.

A trapdoor (locked with a bicycle chain) leads to a ladder for tip top roof access.

Easiest way in is from the skyway/habitrail. You can almost make out the building through the plexiglass celing:

Entrance is at far right.