On the evening of May 27, 1971, shortly after 21:00, a train made up of two class VT 95 railbuses of the Deutsche Bundesbahn was running as special service Eto 42227 (units 795 375 + 995 325) on the single-track line between Wuppertal-Oberbarmen and Radevormwald, the Wupper Valley Railway [de].

The train was filled with senior year pupils of a Radevormwald middle school, their teachers and accompanying railway staff, on the return journey from a class trip to Bremen.

The freight train passed the entrance signal as normal and proceeded slowly into the station, expecting the signalman's instructions.

The motor coach of the two-car special train was compacted to one third of its length and pushed backwards 100 metres (330 ft) by the freight locomotive, which was five times as heavy and whose front wall (without the driver's cab) was 20 centimetres (7.9 in) higher than the railbus.

The signalman at Dahlerau tried to stop the departing freight train by running alongside it and giving emergency signals, but failed to get the driver's attention.

Thanks to quick rescue and medical treatment, 25 people survived despite severe injuries, but 41 pupils, two teachers, a mother and two railway staff died.

Some of the funeral homes that were asked to supply coffins at night time first thought they were receiving prank calls due to the supposed improbability of such a severe accident.

The exact sequence of events was never determined, as the Dahlerau signalman died in a car accident shortly after the train crash.

The driver of the freight train, who survived the accident, testified in court that he saw a green light from the signalman's hand lamp, signalling him to pass through the station without stopping.

As a consequence of the incident, the Deutsche Bundesbahn removed the coloured lens from the hand lamps, which could previously be switched between showing a green and a red light, to avoid the risk of confusion.

The funeral took place on June 2, 1971, a remarkably hot day, and was attended by about 10,000 people, among them Chancellor Willy Brandt, the Minister of Transport and the president of the Bundesrat.

In 1972, a stone pillar containing the inscription "Von den vier Winden komme Geist und hauche über diese Toten, auf dass sie wieder lebendig werden" (Ezekiel 37.9, translates as "Come from the four winds, O breath, and breathe upon these slain, that they may live") was placed next to the graves.

The line only continues unto a point a few kilometres south of the station; the remaining length of track to Radevormwald was flooded during the construction of the Wupper Dam in the 1980s.