The numbers inside some tiles are for a d6 roll that determines the way you enter: in this game you don't put the map as you wish and becomes a new challenge. The arrows indicate a fall making easy go that way but harder going opposite direction. 

In Into the Woods there's a North direction and all moves that way have a chance to find clues to reach your final destination. You can go through the "walls" as well but with the risk of calling unwanted attention. 

Last night I wondered if I could do something similar in n urban environment. I think I will end up making a trilogy...