1142 – Cahir Castle, Co. Tipperary Once the stronghold of the powerful Butler family, the castle retains its impressive keep, tower and much of its original defensive structure.
1142 – Mellifont Abbey, Co. Louth Mellifont was the first Cistercian monastery to be established in Ireland. Founded in 1142 by St. Malachy, the monastery was consecrated in 1157 at a great national synod attended by seventeen bishops and the High King.