World War II left all the bridges over the Rhine in Cologne badly damaged, necessitating the building of new bridges across the river. During the construction of one such bridge, the Severinsbrücke, a terrible accident occurred, killing five workers—according to the official count. The incident has been kept very secret, so secret that even many citizens of Cologne do not know about it. However some disturbing details about the mysterious tragedy have recently come to light.

There’s reason to believe that the number of victims was much higher than five, and that the bodies of the victims, mainly illegal workers from Italy and former Yugoslavia who were not trained construction workers, were left behind in the collapsed pylon of the bridge, buried under tons of concrete.

Construction began on the Severinsbrücke bridge in May 1956. It was inaugurated three years later supported by a pylon 77 meters (250 feet) tall. Today, inside that pylon is a hidden grave of a man killed during the terrible accident that happened in the morning of September 21, 1956.

The accident occurred while the men were working down at the bottom of Rhine River protected by a drop shaft. The drop shaft slid down one side, and five men were killed in the water of the Rhine. Their bodies were recovered, but there is no plaque at the bridge memorializing the victims of the accident, and the whole subject would have been forgotten if documentary filmmaker Hermann Rheindorf hadn’t gone digging.

In his research for a film about Cologne’s bridges, Rheindorf found hints that there was more to the accident than had been revealed. He tried to request an inspection of old records, and police said they could not find them. The historic archive of Cologne collapsed in 2009 and, conveniently, the files about the accident are among the documents that were lost.

Intrigued, the filmmaker went in search of eye witnesses. He met a firefighter whose father who was a policeman at the time of the accident, and told him that several victims are still buried in the pylon. A former worker of the nearby “Deutz” port confirmed that at least one victim is still in the pylon of the bridge. The daughter of Gerd Lohmer, the architect of the bridge, has said that her father was always depressed when he thought about the bridge. He, too, told his family about the secret grave in the pylon. 

Exactly how many victims the accident caused and how many bodies are buried in the pylon, only the supervisor of the construction, Josef Roth from Aschaffenburg, can know. But he was the first victim recovered from the Rhine River 60 years ago. What really happened on September 21, 1956? How many men found their grave under tons of concrete in the pylon of Severinsbrücke?