Some parts of the walkway have completely collapsed and have been replaced by a beam and a metallic wire on the wall. Many people have lost their lives on the walkway in recent years. After four people died in two accidents in 1999 and 2000, the local government closed the entrances. However, adventurous tourists still find their way into the walkway.
It actually reminds me a lot of the new footage for Mirror's Edge, now that I think about it... only with a lot less shooting and cops :)