The old Madrid Burgos line had a collapsed tunnel near Somosierra.
When a landslide caused the derailment of the train between Gumiel de Izán and Fontioso in 2010, ADIF, the state-owned railway infrastructure company in Spain had a very straight solution: Abandon the Somosierra tunnel all together and replace it with a bus service.
The decision makers at ADIF thought, after all, there were not many passengers using the train service. Only 6 at the time of the collapse. So there was this bus which took passengers from the departure station and stopping at every railway station until the destination station.
Remember when long hair on lads just meant that they were hippies