Built around 800AD, Cahercommaun is situated on a burren hilltop over looking a wooded valley. Its structure comprises three concentric walls that abutt a cliff edge very similar to the Dun Aenghus Fort on Inis Mor (Aran Islands). The inner wall was almost a complete circle before the northern section fell down the cliff on which it is built. The outer walls were connected by subsidiary walls, the outer wall measuring 105m east-west and 75m north-south. The inner wall is 1.5m thick and just over 1m high and around 10m from the inner caher.
Archaeologists who excavated the site in the 1930's concluded that Cahercommaun was probably home to an extended family of about 40 people. Family groups such a these would have depended on argriculture. Trade would have been quite limited so it is likely that these family groups were largely self sufficient.
Artefacts such as spindles were discovered which would have been used in the process of weaving. While very little is known about the origins of this fort, a beautiful silver brooch uncovered in one of the souterrains, and now in the National Museum of Ireland in Dublin, shows that it was already in existence by the 9th century A.D.
On a clear day, you will be rewarded with some of the most panoramic views in the county.