An accident
Back in 1934, the train that went through Dundas Peak had a terrible accident. There was a derailment of some of the train cars that flew off the tracks and killed fifteen people. It was a national story at that time and there was a day of mourning in Canada for those passengers.
After that, the route had to be redone and a lot of improvements and inspections were made so that it would never happen again. But that isn’t where the story stops there, it is only where things get really interesting. It could explain just what was in Kim’s cousin’s photograph and make sense of it all.