Early Stone Fortifications

Dún Aengus on the Aran Island of Inis Mór is the West of Ireland's most famous ancient monument. Consisting of a daunting half-circle of stones abutting onto an almost 200-foot high sea cliff, and further fortified by outer walls partially protected by stones stuck upright in the ground, known as chevaux-de-frise, it could have been built for defence (or even ritual) any time within a millennium of the birth of Christ. The same vague dating applies also to other notable round stone forts such as Staigue Fort on the Iveragh Peninsula in Kerry or the Grianán of Aileach in Donegal, which share with Dún Aengus the presence of interior platforms reached by stone stairs. Tradition ascribes the building of Dún Aengus and other, smaller, Aran Island forts to the Fir Bolg (Belgae), one of the prehistoric invaders of ancient Ireland. Their masons knew well how to build solid and lasting walls without the use of mortar, similar skills being noticeable also in many other smaller versions, usually known by the name of caiseal or cashel, and possibly of early medieval date.

Similar stone-craft can be noted as early as around 2000 B.C. with the building of stone walls enclosing very large fields, such as the Céide Fields in Mayo - the ancestors of the wonderful stone walls which, like a hair-net, cover the landscape (or should we call it stonescape?) of the west of Ireland down to our own day.