Mammoth Cave Hindleg
Archived: 19 September 2026
About 31,187 BCE, Ireland lay within the climatically unstable Late Pleistocene, not a recoverable historical year. Radiocarbon calibration permits only broad chronological ranges. At Derryvree, County Fermanagh, freshwater sediments between glacial tills record a locally ice-free, cold, treeless tundra interval, although not an ice-free island. Castlepook Cave, County Cork, contains diverse fauna, including a reindeer femur possibly cut with a stone tool. If confirmed, this may indicate early human activity, but proves neither settlement nor continuity. No institutions, culture or migration route can be identified. Environmental shifts, advancing ice, coastlines and sparse evidence define threshold period in Irish deep history.