I got into OpenTTD when I realized that it was a major source of inspiration for Factorio. Some notes: * OpenTTD is more "purely" about transportation. While Factorio has very good train-logic (block-signals vs chain-signals), OpenTTD has bridges, tunnels, terrain modifications, basic signals, path-based signals, entry/exit signals and more. OpenTTD Trains slow down going up hills and around turns: meaning optimal tr…
Not technically true since you can mix carriages, but like in Factorio having mixed trains is probably a bad idea.