Ancient stone circles in Norway were hiding a dark secret: dozens of children's graves

Archaeologists are mystified by the discovery of dozens of Bronze and Iron Age graves of children in southern Norway.

The burials, each marked by circles of meticulously placed stones, were found by a team from Norway's Museum of Cultural History last year near Fredrikstad, about 50 miles (80 kilometers) south of Oslo, near the Swedish border.

"They've lain here as a secret until we found them," museum archaeologist Guro Fossum told Science Norway. "We uncovered one after another and ended up with 41 round stone formations." 

The circles of stones, which measure up to 6 feet (2 meters) across, were placed together like street cobblestones but were buried a few inches below the surface.

Several circles were placed around a large, central stone, and further investigations revealed burned bones and pottery shards beneath those stones.

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Now, a new analysis shows that almost all of the burials contained children who died between 800 and 200 B.C. Many of the children were infants, and others ranged from 3 to 6 years old.