Clonmacnoise

Saint Ciarán founded this monastery in 544 where the great east–west land route, the Slighe Mhor, meets the Shannon after crossing the bogs of the Esker Riada, and that position made it, by the ninth century, a major centre of religion, learning, craftsmanship and trade, visited by scholars from all over Europe. Many high kings of Tara and of Connacht are buried here. It was largely abandoned by the end of the thirteenth century. Nine ruined churches remain, with a castle, two round towers and a great many carved crosses and cross-slabs.