Derryvree’s Threeleaf Horizon
30,776 BCE is a modern chronological label, not a year for which Ireland preserves an event, a named person, a settlement or a calendar. It falls roughly 32,700 years before the radiocarbon convention of AD 1950, within the Late Pleistocene and Marine Isotope Stage 3 (MIS 3), an unstable part of the last Ice Age. Modern calendar-year precision is not available at this depth. The responsible history of Ireland must therefore be built from sediments, fossil plants, insects, animal bones, cave minerals and radiocarbon measurements, all of which illuminate ranges of time rather than one numbered year.