Castlepook’s Open Season
In archaeological convention, “before present” means before 1950, while radiocarbon measurements require calibration before they can be expressed as calendar ages. Those procedures produce probability ranges rather than annual anniversaries, especially this far back. Around 31,845 BCE—roughly 33,795 years before 1950—Ireland was approaching the major expansion of the last British–Irish Ice Sheet, but was not necessarily uniformly ice-covered. The island’s conditions differed greatly between regions and changed repeatedly over long human timescales.