"Now it turns out that more than 400 points on the railway network need to be checked. And if we do nothing and don't complain, we'll just keep running as if nothing's wrong and see if another tragedy doesn't happen? That can't be. We want a structural reform and greater safety," argue sources from Semaf, the largest train drivers' union. "We thought we knew the most complicated areas, and we already thought there were many, but they weren't all of them. But we see the most serious problems: crooked trees, potholes... When you go through a tunnel, unless a piece falls, you don't know if everything is okay or not," argues Francisco Cárdenas, a train driver with more than four years of experience.