In 1979 Disneyland built its Big Thunder Mountain Railroad ride around a runaway-mine-train theme complete with caves, mineshafts and a desert landscape. That premise became all too real in 2003 when part of a train actually derailed, killing one rider and injuring 10 others.
The train, which consists of a small locomotive and five cars that can carry 32 people, had just shot up a hill and into a tunnel when the accident happened. A wheel assembly fell off the locomotive, jamming one of the axles and causing the back end of the locomotive to kick up and hit the top of the tunnel. The front car then struck the locomotive's undercarriage, killing one man who had to be extricated from the wreckage by emergency workers. When the dust settled, the locomotive sat derailed at the top of the hill while the remaining cars stayed on the tracks and came to rest 20 to 30 feet (6 to 9.1 meters) away at the bottom of the incline [sources: Pfeifer et al., Luna].
Investigators from the California Division of Occupational Safety and Health (Cal/OSHA) later released a report blaming park maintenance workers, ride operators and a mechanic for the accident. Disney settled with the deceased rider's family for an undisclosed amount of money.