The bone fragment, which bears chop marks consistent with butchering with a flint or stone tool, was found at Castlepook Cave near the town of Doneraile in Ireland’s Ancient East.
Situated in the foothills of the breathtaking Ballyhoura Mountains, the cave was originally excavated in the early twentieth century by naturalist Richard Ussher, who found a high volume of woolly mammoth and other animal remains.
Following excavation the material was shipped to the National Museum of Ireland and stored in boxes on shelves for more than one hundred years.
It wasn’t until a bone fragment from the hind leg of reindeer femur was sent for examination that scientists realised its potential to transform the story of Irish human history.
Analysis of the bone establishes human activity in Ireland 33,000 years ago, more than 20,000 years earlier than had previously been believed.
Up to now the earliest evidence of human activity had been a butchered bear bone found in a cave in County Clare, which was dated at 12,500 years old.
The story of the discovery was revealed as part of The Burren: Heart of Stone, a documentary by filmmaker Katrina Costello broadcast on national Irish TV channel RTÉ 1 in April.
The two-part documentary, narrated by well-known Irish actor Brendan Gleeson, traces the history of The Burren, one of Ireland's most wild and wonderful natural environments and an area packed with mystery, rocky landscapes, deep caves and ancient dolmens.
With the process of the archaeology going on all the time, the Irish landscape continues to throw up amazing discoveries from its storied past.