Mystery of the massacre in the cave more than 1,000 years ago

Dunmore Cave is a cave located in southern Scotland and was discovered in 2017. In the cave, archaeologists found hundreds of human bone fragments and many objects, including silver and bronze objects.

Dunmore is a cave system in County Kilkenny, formed over millions of years when melting glacier water dissolved limestone through a chemical process. It is one of the largest natural caves in Ireland, running approximately 402m long and reaching depths of 46m.

Stairs leading to Dunmore Cave. (Photo: Mark Heard/Flickr)

One of the earliest accounts of the Dunmore Cave Massacre comes from Bishop George Berkeley. He visited Dunmore Cave as a boy in the early 1700s and remembered hearing about the bones piled up in the dark cave. However, the story behind the victims has been disputed for many years.

According to the "Annals of the Four Masters" , a chronicle of Irish history from ancient times up to 1616, Derc Ferna - likely the old name of Dunmore Cave - was the site of a massacre in 930. Gofraid ua Ímair, the Viking leader in Dublin, sacked and destroyed Dearc Fearna, where 1,000 people died that year.

Archaeological evidence cannot confirm the exact events described in the chronicles. However, experts found a large number of human bones in the cave during an excavation in 1869. In 1973, archaeologists discovered the remains of 19 adults, 25 children, and a series of silver coins dating from around 930.

Some have speculated that the remains in Dunmore Cave may be soldiers from the Irish Eleven Years' War (1641-1653) or victims of the Irish Rebellion of 1798. However, a 2004-2005 study that radiocarbon dated the skeletons ruled out the possibility that the remains were from the 1798 Rebellion or the Eleven Years' War and found that many of the remains date to around the 10th century, matching accounts of the Viking massacre in 930.

Archaeologist Neil Jackman theorizes that the locals fled into Dunmore Cave when they heard about the Viking invaders. This is why there are so many children and women among the remains. The Vikings lit fires at the cave entrance to force the people out with smoke and capture them to sell in the slave market. This also explains the discovery of some of the charred stones and bones in the cave. Eventually, the cave filled with smoke and ran out of oxygen, killing everyone who took refuge inside.

However, many questions remain about Dunmore Cave. Despite its Viking connection, it is possible that the remains in the cave are not evidence of a massacre but simply a Viking burial site, similar to others in Ireland.

"Was Dunmore Cave a burial site or the site of the massacre recorded in the chronicles? Do the remains belong to Vikings buried in 'pagan' lands or to innocent victims of a Viking massacre? Only further research and excavation can shed light on these important questions ," the authors of a 2007 study concluded.