Castlepook Uncertainty
Archived: 9 September 2026
Around 34,000 calendar years ago, corresponding to 31,907 BCE, Ireland lay within the climatically unstable Late Pleistocene MIS 3. Lower sea levels and variable ice margins created changing landscapes, not a fixed land bridge or wholly glaciated island. Derryvree sediments in Fermanagh indicate open, periglacial tundra supporting cold-adapted vegetation and animals. Castlepook Cave in Cork preserves Ireland’s richest Pleistocene fauna, including mammoth, reindeer, hyaena, bear and lemmings, though old excavations complicate interpretation. A reindeer femur possibly marked by a stone tool may indicate a human visit, but cannot demonstrate settlement. Subsequent glaciation obscured evidence; Castlepook remains an unresolved archaeological question.
