Ancient cave art pushes back human settlement of Ireland to 15,000 years ago

When the last Ice Age gripped the British Isles, the sea level dropped so far that a corridor of land emerged between what is now Wales and the south-east coast of Ireland. For thousands of years, this pathway—a forested and grassy plateau stretching roughly 46 miles across—connected two worlds that are now separated by water. Researchers have long suspected that hunter-gatherers would not have ignored such an opportunity. Now they have found the proof.

Dr. George Nash, a rock art specialist at Liverpool University, led an international team that located eight cave sites in south-west Ireland bearing rock art dated to at least 15,000 years ago. This discovery pushes back the known human settlement of Ireland by roughly 5,000 years, challenging the previous archaeological consensus that humans first arrived around 10,500 years ago. The finding emerged from the Lost Land Bridge Project, a collaboration involving researchers from University College Dublin, the University of Adelaide, and institutions in Dubai, Wales, and Portugal.

The pathway itself would have been a hunter's landscape. During summer months, temperatures hovered between minus 10 and minus 20 degrees Celsius. Wild horses, mammoth, bison, and reindeer roamed across sedges, mosses, and lichens that clung to the frozen soil. Nash believed from the start that early humans would have seized this advantage. "Everyone knew that simply couldn't have been correct," he said of the previous 10,500-year estimate. "We just weren't looking hard enough, and not in the right places."

The breakthrough came through artificial intelligence. Working with caving specialist Shane Diffily and digital mapping consultant Darren Lee, Nash's team fed a computer algorithm with everything known about the characteristics of cave dwellings in south Wales. The model then searched for matching sites across Ireland without requiring researchers to wander the countryside hoping to stumble upon something promising. The algorithm identified 28 potential caves. When the team investigated them, eight contained cave art.

The artwork itself tells a story of human presence and artistic progression. The team found engravings on cave walls, paintings in ochre and charcoal, and line sketches pressed into clay and earth by fingertips. Nash traces a lineage back to south Wales, where modern humans settled between 35,000 and 40,000 years ago, having crossed dried-up land bridges from southern England, France, and Spain. Over 20,000 years, their art evolved from what may have been primitive tally marks to more representational depictions of their world. The Irish cave art represents yet another stage in that progression.

The team has chosen not to disclose the exact locations of the caves, fearing vandalism or looting. But Nash sees the discovery as the beginning of a larger reckoning. Population pressure in south Wales likely drove people westward and northward. On the Gower Peninsula alone, around 100 human-inhabited caves existed at a time when people had not yet developed the technology to build free-standing structures. Caves maintained temperatures between 10 and 15 degrees Celsius year-round—warm enough with bearskin covers and fires at the entrance to provide shelter and protection from predators. Competition for these spaces would have been intense. As family networks grew and knowledge of animal migration routes improved, people became bolder in their movements.

Nash is convinced that more discoveries await. "It's illogical to presume that early humans just bypassed Wexford, Waterford and Cork, and ploughed on west," he said. The sites explored so far lie in south-west Ireland, but the team expects to find earlier settlements across the southern counties. The project is redefining what researchers consider the frontier of north-west European human habitation, pushing the timeline back and expanding the map of where our ancestors ventured during the Ice Age.