Castlepook Before the Ice Sheet
Archived: 17 September 2026
At 31,494 BCE, Ireland lay within the climatically unstable Late Pleistocene MIS 3. Derryvree’s dated freshwater sediments show that parts of north-central Ireland remained ice-free, supporting treeless tundra wetlands, before later glaciation. Castlepook Cave in Cork preserved bones of reindeer, mammoth, giant deer, hyaena and other Ice Age fauna, although its deposits span long periods and are partly disturbed. A marked reindeer femur may indicate human butchery about 33,000 years ago, but requires confirmation and cannot establish settlement. No evidence supports contemporaneous polities, agriculture, villages or culture. Changing sea levels and uncertain routes connected an ecologically diverse, archaeologically elusive island.