So there I was, building a rail line through the jungle, when I reached a point on the map at which it made sense to place a roundabout. As I started in on the build process I’ve used a couple dozen times now (type ’roundabout’ into the search field to see other posts about the development of this process) I realized that the requirements of the approach and exit placement weren’t going to fit the location. I needed an alternative.

At first I thought of doing a criss-cross interchange but I prefer having the option of letting a train loop back around if necessary at every one of these intersections. Still, I figured that an interchange would probably fit this particular location better than a roundabout so I went looking for information on how best to build one.

I didn’t find that. Instead, I found guidance on how to build a different style of roundabout, approaching it as more of a modified diamond than a rounded square. The difference is largely academic in the long run, but the practice of building it is definitely trickier.

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