Derryvree Between Two Tills
This was long before Irish written history, agriculture, monuments or identifiable peoples. It also preceded the climatic low point conventionally called the Last Glacial Maximum, dated globally to about 26,500–19,000 years ago. Ireland was not yet uniformly buried beneath the ice sheet that later reshaped much of the island. Evidence from sediments, fossil remains, cave deposits and ice-sheet reconstructions instead indicates a varied and unstable world: some districts were ice-free, conditions were cold and strongly seasonal, and the growth of the last Irish Ice Sheet still lay ahead.