Insula Sanctorum et Doctorum; Or, Ireland's Ancient Schools and Scholars

by John Healy

The plan of Dun Ængus can be much better understood since the recent restoration effected by the Board of Works. This wonderful fort occupies an angle of the cliff, and in outline is semi-elliptical, with the diameter resting on the edge of the cliff, which itself formed a natural and impregnable wall on the sea side. The fort consists of a triple line of defence, and thus included a triple area rudely concentric. The wall of the inmost area is eighteen feet high, and about eight feet thick. It was built without cement of any kind; but really consists of two separate walls built close together of stones moderate in size, but carefully laid in horizontal positions. This inner wall surrounds a bare rocky floor, now covered with green turf, 142 feet along the cliff’s edge, and about 150 feet in depth from the cliff to the furthest extremity.

This inner wall had an entrance some 3 feet 4 ins. wide, and quite perfect when visited by John O’Donovan in 1839; but its lintel has since been thrown down, and the margins broken. It has, however, been lately restored by the Board of Works. The middle wall is at a considerable distance from the inner enclosure, in some places more than 200 feet, but on the north-western corner, where it approaches close to the cliff, it is not more than 22 feet from the inner wall. Outside of this second wall there is a very extraordinary cheveaux de-frize, consisting of large sharp stones set upright, so sharp and so closely set that even to this day it is impossible for man or beast to make their way through them, even with the greatest caution, without cut shins, if nothing worse should happen. We have ourselves tried the experiment, and we did not escape scathless. Nothing more efficacious to break the ranks of an advancing foe, whether horse or foot, could possibly have been devised.

Beyond this cheveaux-de-frize there are the remains of a third wall, which enclosed a very considerable space, and terminates, like the other two, on the very edge of the stupendous cliffs.

This fort of Dun Ængus, with its triple walls, and its chevaux-de-frize, defending it all round to the edge of the cliff, was a fortress so formidable that even still a hundred resolute men could hold it against an army, at least so long as artillery was not employed to dislodge them.

Dun Conchobhair, or Conor’s Fort, on the Middle Island is a still more astonishing structure, if we have regard to the time when it was built. Tradition ascribes the building of this noble fort to Conor, another son of Hua Môr, and brother of Ængus. It is larger, and better built than the Fort of Ængus, and is finely situated in the centre of the island at its highest point about 250 feet above the sea. The innermost enclosure measures 227 feet in length by 115 feet in breadth, and is oval in form. The wall had two faces and a central core; it has besides a considerable batter, and varies in different parts to from five to eight feet in width. On the east side there was a triple wall nearly eighteen feet in breadth, and twenty feet high. Its summit seems to have been approached by a flight of lateral steps in the wall, of which the traces still remain.

In this, as well as in some of the other forts, are the remains of cloghauns, or small cells, of beehive shape, built of stone, which were evidently the habitations of the defenders of the fortress. This fact is highly important, because it goes to show, that the beehive cell of the early saints within the caiseal or sacred enclosure was not a new idea, but simply the practice, which the saints had themselves seen in those pagan forts, where stone abounded.

There is another fort called Mothar Dun, on the Middle Island, which is both in size and outline merely a reproduction of Dun Oonacht, to which we shall presently refer. Its largest diameter is 103 feet, and its smallest 93 feet. It was so situated on the slope of the hill, that the summit of the rocky cliff overlooks the area of the fort.

Dubh Cathair, the Black Fort, is in the townland of Killeany, on Aran Mor. It was situated on an isolated promontory rising high above the sea, and separated from the mainland by a wall and fosse about 220 feet in length. The fort takes its name from the black colour of the stones with which it was built.

Dun Oonacht is also on Aran Mor, at its northern extremity, and commands a magnificent view of the coast line and mountains of Connemara. In shape it is nearly circular, with a diameter of 94 feet, and is built of large stones, laid horizontally, but not in courses. The fort wall was very much broken; it has, we believe, been repaired since our visit, but it is still quite 15 feet high on the southern side. There are no traces of a chevaux-de-frize, as at Dun Ængus, and at the Black Fort. Dun Oghil is also in Aran Mor, and crowns the summit of the highest hill on the island. It has two concentric enclosures, the inner of which is an oval 75 by 91 feet. The name meant the Fort of the Yew Wood.

There was another large fort on the Southern Island, but even tradition has forgotten its name. There are also other remains of a similar character in these islands, especially on Aran Mor, but even their names have vanished from the tenacious memory of the islanders. At least one of these ancient forts, the Dun of Muirbheach Mil, was utilized in Christian times as a monastic enclosure, within which the oratory and the cells of the monks were constructed. It is not unlikely that all the stone caiseals on the shores and islands of the West, were similarly of pagan origin, but were utilized by the monks to protect their own religious buildings.