Does a road have to be on the surface?
I have dug a tunnel from inside my fort to the edge of the map. Will this work as a road connected to my town hall in order to attract immigrants, or does the road have to be on the surface?
Solution 1:
In order to attract Immigrants and Traders the road must be on the surface at the end of the map.
It can be underground all the way there, however the last part must be on the surface in order for it to work. I don't have any proof for that as I simply tried it myself.