Threeleaf Under Drumlin Clay
Archived: 7 October 2026
Around 30,137 BCE, Ireland lay within the climatically unstable Marine Isotope Stage 3, and evidence permits no precise annual reconstruction. At Derryvree, County Fermanagh, organic sediments between glacial tills record a temporary, cold ice-free wetland, with grasses, sedges, bogbean and water-milfoil, later buried by advancing ice. Castlepook Cave, County Cork, preserves fauna including reindeer, mammoth, giant deer, bear, hyaena and Arctic lemming, indicating links with wider Europe. A possibly cut reindeer bone suggests, but cannot confirm, human visits. No settlement, tools, institutions or culture are securely attested. Ireland was a dynamic, intermittently habitable landscape approaching more extensive regional glaciation soon.