The Maguiresbridge Tundra Basin
Archived: 27 September 2026
About 30,557 BCE, Ireland’s evidence records no datable event, but Derryvree near Maguiresbridge preserves freshwater sediments deposited between glacier advances during Marine Isotope Stage 3. Their broad calibrated range encompasses this notional date, indicating an open, cold tundra wetland with pools, sedges, dwarf willow, mountain avens, mosses and seasonally available water. Local ice had retreated temporarily, although the British-Irish Ice Sheet was growing towards its later maximum and national conditions remain uncertain. Castlepook Cave’s fauna, including reindeer, mammoth, predators and other cold-adapted species, demonstrates variable food webs. A possibly butchered reindeer bone suggests transient Upper Palaeolithic visitors, not proven settlement.