More than a century ago, one of the most valuable collections at The National Museum of Denmark – the remains of a Viking believed to be related to Harald Bluetooth – mysteriously vanished.

But thanks to some sterling sleuth work by the museum’s own archaeologists, Ulla Mannering and Charlotte Rimstad, the long-lost bones have been recovered.

The pair managed to find the collection of bones in a storage box, which contained the remains of a different Viking burial site.

“We’ve always had a feeling that they had to be in the museum somewhere. They have been searched for many times, but it is only by chance, here more than 100 years later, that we stumbled upon them in a box where they shouldn’t be,” Ulla Mannering told DR Nyheder.

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Discovered in 1868
In 1868, a local farmer in Mammen, near Viborg, discovered the Viking tomb that contained numerous valuable objects.

The Mammen Grave stems from 970-71 AD and contained the remains of a man in a wooden chamber grave.

The man wore valuable clothing made of silk, with a large wax candle, and an ax laying at his feet. It is believed that he may have had close relations with legendary Viking king, Harald Bluetooth.

The remains from the Mammen Grave and other objects from the Late Iron Age and Viking Age are on display in Denmark’s Antiquity Exhibition at The National Museum.