Bioshock Infinite type Skyline?

http://www.youtube.com/watch?v=2XyJba0hVME

After seeing this yesterday i've been trying all morning to try and recreate it. Anyone have ideas how should go about it?

It would be good fun to learn!

I usally use Java script or C++ for my scripting!

Maybe something like when player is in target region of skyline/zipline have it attach to a game object which is instantiated on the skyline. Then hand over movement controls to the gameobject which you need to create a way of restricitng the movement to the skyline. (not sure how but I would try a waypoint and raycast system although I myself am not good enough to create this) Good luck, would be interesting to see how you've done it once you succeed.