Factorio Forums

I'm having a problem with my trains crashing into themselves on roundabouts. I'm not sure if this is a bug or not but I believe its caused by pathfinding problems for the train routes

Simple answer : your trains are too long for your roundabouts.

Either use shorter trains (which has its own issues) or design larger roundabouts. Or, just get rid of the roundabout idea entirely, and design different intersections.