Hi, you can easy create with standard terrains. Just create your Mountain and copy&paste it.. You need it for a Shape. After this design your roads at the mountain and cut them off or for smaller scenes but the 2 terrains together so we get the different between.. Sorry not easy for me to write in english:)

But maybe it woud help you search a tut about lakes, rivers or waterfalls.. its form the idea behind it the same... at rivers and lakes wie cut some out and at roads we attach some.

 

bye and good luck