Here's my sketch for the final version of the Lionsgate City Underground board. The idea is a series of caves connected by tunnels. Players move between caves through tunnels, and can also block tunnels with their train cars. There are five kinds of caves: Mines, where ore is dug up, Towns, where it is sold, and the Mercenaries' Guild, Sheriff's Office and Vault Exit, each of which has a special function in the game.
If you want to learn more about the game, you can read the rules here: https://docs.google.com/document/d/.....it?usp=sharing