So I'm working on my Blacktown at the moment, and according to the backstory, the town is built on the top of a cliff with some residences at the bottom. I want the people in the houses below the cliff to be able to get up top, but I also want the cliffs to actually be steep enough that they're totally unroutable. My two options are to either create a path that's been cut out of the cliffs or to use the subways, but I have no clue if the subways will work over unroutable terrain since Bridgeport busts my computer up. Can anyone give a definitive answer?