Periglacial Environment
Archived: 18 September 2026
Abstract
Around 31,354 BCE, Ireland lay within the unstable MIS 3 Ice Age, although no event can be assigned to that year. Derryvree, County Fermanagh, provides the best local evidence: organic sediments dated broadly to 36,900–31,700 calibrated years before present record an ice-free, treeless periglacial wetland between glacial advances. Sedges, mosses, hardy herbs, insects and shallow pools formed a varied tundra-like landscape. Castlepook Cave reveals that mammals including mammoth, reindeer, giant deer, bears and hyaenas reached Ireland during MIS 3, but not necessarily together. Human presence remains unproven. Ireland was approaching renewed extensive glaciation, with no evidence of society or trade.
