Derryvree’s Freshwater Tundra
The closest important Irish environmental record is at Derryvree, near Maguiresbridge in County Fermanagh. Road-cutting through a drumlin in 1969 exposed organic silts and fine sands sealed between two separate till sheets. The deposit produced a conventional radiocarbon determination of 30,500 +1,170/−1,030 radiocarbon years BP. When calibrated, such an age belongs within a wide span of the later 30,000s to early 30,000s cal BP rather than a single year; it is broadly relevant to the nominal date of 31,814 BCE. The uncertainty is not a failure of scholarship but an honest consequence of the radiocarbon curve, sample limits and the long timescales involved.