In Paris, you have the national train company (SNCF) who competes with the Parisian subway system (RATP). To make matters even more complicated, some suburban r

In Paris, you have the national train company (SNCF) who competes with the Parisian subway system (RATP). To make matters even more complicated, some suburban rail lines are operated by one over the tracks of the other. This is seamless until one of them goes on strike... For the geek part: when trains shift from one network to the other (RER B between Châtelet and Gare du Nord), they free-wheel while they transition power from one network to the power of the other one. On the rare occasion that a train has to stop in the middle of that dead zone, it can't move anymore...