There are train lines that start out from a home station and spread across a map of the USA, and there are cards you play to claim your part of the payoffs, so it's reasonable to view Santa Fe as a predecessor to Union Pacific. Alan R. Moon says he designed Santa Fe after he saw Wildlife Adventure for the first time and enjoyed its line-extension mechanism. It's got a couple of tricks of its own and, though you can certainly be dealt out of the competition simply by the cards you get, it's still quite interesting to play. - BoardGameGeek