Castlepook’s Reindeer Dilemma
Archived: 20 September 2026
About 31,006 BCE, Ireland lay within the fluctuating cold conditions of Marine Isotope Stage 3, not a datable historical year. Organic deposits at Derryvree, Fermanagh, preserved between glacial tills, indicate treeless freshwater wetlands during an ice-free interval, while related northern sites confirm episodic, uneven glaciation. Castlepook Cave, Cork, contains reindeer, mammoth, giant deer and predators, demonstrating access for large mammals across changing landscapes. A marked reindeer femur, possibly cut by a stone tool, may indicate brief Upper Palaeolithic human activity, but lacks secure archaeological context. No settlement, community or culture is established. Subsequent ice, erosion and rising seas obscured evidence.