It is February 20, 1946 in Bergkamen: At 12 noon, a firedamp explosion at a depth of 900 meters triggers the worst mining accident ever in Germany. The explosion is so violent that a 300-meter-high jet of flame bursts from the entrance shaft of the "Grimberg 3/4" mine. Just 1 year after the end of the war, 405 miners die. They leave behind 283 widows and over 400 children. Only 64 miners can be recovered alive because of inadequate equipment for the miners and the recovery teams.

This event is deeply etched in the collective memory of the people of Bergkamen and the entire Ruhr region. Many Bergkamen residents grew up in the so-called "widows' quarter" and to this day have a "family" relationship with the mining accident at the so-called "Zeche Kuckuck".