If you think you have what it takes to build and manage a connect network of rail tracks, Rail Route is a game you might want to go and take a look at.
Unlike the much bigger and more graphically impressive tycoon sims like Transport Network and Railway Empire, here it's not about getting resources around. Rail Route pulls things back to the basic level of working with railway network lines and the management that comes along with it - the art of dispatching trains and getting them around on time. It's almost like the Factorio of rail simulation. You constantly expand as you accept new contracts and build up an ever more complicated series of lines along with plenty of automation.
It mixes the gameplay between endless maps to just do whatever you want, along with score-based maps that act more like puzzles featuring hand-made timetables of famous and imaginary junctions / layouts. There's also an in-game editor to get creating and sharing across the Steam Workshop.
This is just the start of the journey for the game, with lots more planned. They want to add in shunting, freight yard maps, special map events, more to unlock on endless maps and no doubt plenty more. There's no expected date for it to leave Early Access as they want to keep on expanding it and just get it right.
We played through a bunch of it when they had the demo builds available on itch.io (no longer up) and it was impressive. It does quickly get complicated but it's absolutely fantastic once you get going. With so many moving pieces, it's so easy to get sucked in once you've got a good setup going. There's a short tutorial to get you going which gives you the basics and it's enough to at least let you get started but after that you're mostly on your own. It's good though, allows for plenty of freedom and so far it's been thoroughly interesting.
Rail Route can be found on Steam.