Sandby borg is an Iron Age ringfort on the southeast coast of the Swedish island of Öland. It’s one of many ancient ruins on the island, which is rich in history and nature. What makes this particular fort infamous is the discovery that it was the site of a gruesome massacre that occurred some 1,500 years ago. 

In 2010, archaeologists excavating the site dug up the bones of dozens of humans who had been brutally killed in a mass murder. Researchers suspect hundreds died in an attack that wiped out every last inhabitant of the ring fort at the end of the 5th century, during the tumultuous Migration Period in Europe around the fall of the Western Roman Empire.

The excavations revealed gruesome details of the attack, such as decapitated heads, bashed skulls, and even the remains of children; the youngest victim is estimated to have been no older than 18 months old. Worse still, the bodies were never buried but were left where they fell, in their houses or on the street inside the walls of the ringfort.

The Sandby borg fort now lies in ruins, but the massacre of men, women, and children still lingers in the minds of Öland’s islanders. Elders will tell you about “the dangers of the fort,” even though no one really knows what happened all those centuries ago.

Roman-era artifacts such as glass, arrowheads, and coins have been found at the fort, giving archaeologists a unique insight into life during the 5th century. But the details of the massacre remain a mystery.