Factorio/Satisfactory (the world was implicitly infinite, but increasingly 3D and first-person towards the end of the dream) had gondolas. You could just plop down towers and they'd be connected by cables with cars running back and forth along them. For freight-moving purposes they acted like small, low-capacity trains. The advantage over trains was that they could easily cross over cliffs, rivers, forests, or any other obstacle. And I was off in the boonies to the (let's say) west of my and Sara's base where there was sort of a mountain with lots of cliffs and a river running down the side setting up my first gondola system.

And they were fun to play around with, but then I remembered that the whole point was to connect up with the rest of our base. So I was building gondola towers along the river back towards our base. I had to pass through a canyon, and as I entered it I gave up on the gondolas, I decided that I may as well build a regular railroad through here. I got back to base and started extending a railroad into the canyon. I was going to have to build a lot of 8x8x4 foundations. Sometimes in order to get the tracks to go how I wanted I had to deconstruct them and rebuild them a few times, just like in real Satisfactory.