The Derryvree Drumlin Archive
Archived: 9 September 2026
Around 31,891 BCE, Ireland experienced fluctuating Late Pleistocene cold during Marine Isotope Stage 3, not the later glacial maximum. Derryvree, County Fermanagh, preserves freshwater silts dated broadly to this period, revealing treeless, wet, tundra-like ground between glacial advances. Expanding upland ice, permafrost, seasonal thaw and altered drainage shaped a changing landscape, while lower sea levels modified coasts and possible migration routes. Cave remains show mammoths, reindeer, hyaenas and other mammals occupied Ireland during the wider period. Possible cut marks on a Castlepook reindeer bone may indicate early human visits, but no secure evidence demonstrates settlement, communities, institutions or sustained occupation.