Derryvree’s Periglacial Basin
Archived: 2 October 2026
At 30,346 BCE, Ireland lay within climatically volatile Marine Isotope Stage 3, not a precisely datable historical moment. Derryvree’s freshwater silts, bracketed by glacial tills and broadly dated to 34,950–29,750 BCE, demonstrate an ice-free interval in Fermanagh. Their plants and insects indicate cold, treeless, waterlogged tundra with pools and seasonal growth. Cave finds show that cold-adapted mammals inhabited Ireland at various times, but cannot reconstruct a single landscape. A possibly cut-marked reindeer bone suggests a human visit, not settlement. Lower sea levels and fluctuating ice altered connections, while the Last Glacial Maximum remained ahead. Evidence therefore records dynamic, precarious ecosystems.