Transport tycoon is not only about trains. In transport tycoon you can also use busses, planes and ships. One of the games I have used most time on in my life, is Railroad Tycoon 1, and I liked this game very much. There are some flaws in the game, there is no doubt about that, but overall it's a cool game.
BTW I played railroad tycoon II also, which I also think is pretty good.
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