BIRM-166’s Long Season
Archived: 27 September 2026
About 30,598 BCE, Ireland was not a recorded society but a changing Pleistocene environment within Marine Isotope Stage 3. At Derryvree, County Fermanagh, freshwater organic deposits between glacial tills demonstrate an ice-free wetland interval, dated broadly rather than precisely, amid recurring ice advances. Plants indicate cold, treeless tundra with shallow water and sedge-rich margins. Lower sea levels and shifting ice affected access to Ireland. Cave remains show reindeer, mammoth and other cold-adapted fauna. A cut-marked Castlepook reindeer bone suggests possible early human activity, but confirms neither settlement nor continuity. Together, evidence reveals intermittent habitats supporting life before later maximum glaciation.