Place de Rennes in Paris was built for trams; it was not built for railway wagons, and not for steam locomotives balancing on their noses.
When the No. 56 train from Granville dashed past the first signs announcing Gare de l'Oest (today Montparnasse station), its twelve wagons and the type 120 locomotive propelling them seemed unusually fast. The locomotive's driver and two conductors tried to bring 131 passengers, luggage, mail and several tons of steel to a halt, first (and extraordinarily) with an air brake that failed and then (too late) with hand brakes that didn't help much.
A few minutes past schedule, around 4 p.m., the locomotive with the number 721 arrived at the buffer stop; it was no obstacle. The train continued for some 100 feet (30 meters) through the station hall and met a 2 feet (60 cm) thick wall. Past the wall, the locomotive and the first wagon cruised over a short terrace. Where the terrace ended, the locomotive alone plummeted onto said Rennes square some 30 feet (9 meters) below, missing a tram but tragically hitting a woman selling newspapers.
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