BIRM-166 Radiocarbon Sample
Archived: 5 October 2026
Thirty thousand years BCE is not a recorded Irish date but a calibrated horizon within the unstable Late Pleistocene. Derryvree, County Fermanagh, preserves freshwater organic sediments between glacial tills, dated by BIRM-166 to a broad interval encompassing 30,227 BCE. Its plants indicate treeless, periglacial wetlands with tundra vegetation, later overridden by ice. The site demonstrates local environmental change, not island-wide conditions or a single event. Cave remains at Castlepook show that varied cold-adapted fauna reached Ireland, although their chronology remains complex. A possibly butchered reindeer bone suggests provisional human presence, but no secure evidence confirms settlement, society, or continuous occupation.