Derail Valley: this one lets you actually be inside of a train and transport cargo, has crashes, simulates engine temperature for electric locomotives, even lets you use steam locomotives as well, really interesting Workers & Resources: a city building game with a rather nice transport system, the UI needs work, but it might eventually be up there with Cities: Skylines (at least based on what others say) Railway Empire: focuses only on trains, seemingly the older variety too, has a large amounts of maps and interesting city growth mechanics but the UI isn't as good as TF2 and even though it has perhaps the best track building mechanics, managing lines becomes cumbersome when you have many Mashinky: a mix like the both of the above, developed by a single person, allows switching between an isometric tile based build mode and 3D visualization, currently has a variety of trains and some road vehicles, switches are automatically placed (either chain or regular switches, really nice logic) some might dislike its economy system (some trains need certain resources to run, which you need to get through supply chains, possibly with other trains), but i really like it

Transport Fever (1 or 2): lovely games that have really detailed 3D graphics, the UI/UX in TF2 is the best that i've every played with, however the train pathing doesn't appear to be dynamic, only simple signals present OpenTTD: free, open source, has a variety of transport, even crashes, low hardware requirements, but personally the train tiles aren't easy on the eyes Here's some of the other similar games that i enjoy:

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