The ruins of a Celtic monastery on the east coast of Ireland, one of the best preserved of the early Irish monasteries though possibly of the 8th century. The monastic complex includes two rectangular oratories with fine corbelled roofs, a later chapel, and a series of terrace walls known as the 'monks garden'; there are also six beehive huts in which the monks lived. The island suffered Viking raids but the monastery continued to be used until the 12th or 13th century.