Abbeymahon Abbey is a ruined abbey situated near Timoleague, County Cork, Ireland. It was founded in 1172 by Dermot MacCormac MacCarthy, king of Desmond. The site was originally at Aghamanister and was colonized with a group of Cistercianmonks from Baltinglass. Almost a century lapsed before the monks of Aghamanister decided to move to a new site; it is possible that the time had come to renew the abbey buildings and the monks took the opportunity to find a more spacious site. The monks had moved to Abbeymahon by 1278, when Diarmait MacCarthaig, son of Domnall Cairbrech, was buried in the ‘new monastery’. The new site was on the estuary of the Argideen River, just over a mile east south-east of Timoleague, on the road to Courtmacsherry. The abbots of Abbeymahon were rebuked several times in the thirteenth century for not attending the General Chapter when summoned. It is not surprising that the abbots refused to attend considering that the journey was extremely lengthy and expensive. In the taxation of 1302-1306 the income of the abbey was valued at £4, which would hardly have covered the cost of the journey. The annual income of the abbey during the 15th and 16th centuries was still a meager amount, estimated at just £18, with a potential income of £34 during peace time. At the time of the Dissolution it was found that the abbey church was functioning as the parish church and that all other buildings were being used by the local farmer. In 1568 the property was leased to the Viscount Barrymore and in 1584 the lease was transferred to Nicholas Walsh, Justice of Munster. The site was granted for ever to Nicholas Walsh in 1587, with some additional place names appearing on this grant. The remains consist largely of the east end of the church and some remnants of the tower.