CASTELL COCH, GLAMORGAN.
THE river Taff, from its origin under the Brecon Beacons, after a course of about 26 miles through the northern and mountain district of Glamorgan, escapes by a deep and narrow ravine across the last elevation, and rolls its course, unfettered, to the Bristol Channel.
The ridge which it thus finally cleaves, and which divides the hill country from the plain, is part of the great southern escarpment of the coal basin of Glamorgan, supported there by the mountain limestone rising from below, and in its turn reposing upon the old red sandstone, the denuded surface of which forms, under the later horizontal rocks and drift gravel, the basis of the plain. The escarpment, extending for many miles along the contiguous counties of Monmouth and Glamorgan, is traversed, in this immediate neighbourhood, by the three passes of the Ebbw, the Rhymny, and the Taff. The heights bounding the latter river, though in actual elevation below some other parts of the chain, produce a very striking effect, from the abruptness of their rise from the plain.
These heights, on each side of the pass, must always have been regarded by the inhabitants of the country as places of great security. On the right bank of the river, the huge lumpish sandstone mass of the Garth rises to 981 feet above the sea, and is crowned by two remarkable tumuli, well known as landmarks in the vale, and visible even from the distant shores of Somerset. The lower Garth, which rises to the front of the great Garth, opposite to Castell Coch, forms the right bank of the pass.
The elevation on the left bank, though lower, is more precipitous. It presents, in the lichen-stained crags about its summits, and the rich verdure which clothes its sides and base, all those features so well known to geologists as characterising the scenery of the mountain limestone.
Nature has rendered the west and south sides of this height— those exposed to any foe from beyond sea—nearly inaccessible. Across the north-eastern side, lines of circumvallation have been hewn out of the rock, the dimensions of which show the value attached to the place, as a fortress, by the Cymry.
There was reason in the choice. From hence the long ships of the Danish rovers could be seen while yet distant from the shore, and timely notice be given, and protection afforded to, the people of the plain, should the ravagers extend their sweep far inwards from the coast. A beacon fire upon the headland of Penarth—celebrated in Anglo-Norman verse for its ancient oak, and long marked by its white church—answered here, or on the opposite Garth, would be repeated from the summits of the distant mountains of Brecon and Caermarthen, and would at once spread the tidings of invasion over the whole of the southern coast.
The Normans, within a century and a half after the conquest of Glamorgan, had completed a chain of castles along the plain country, from Chepstow to Pembroke, and were only exposed to the invasions of the Welsh from the mountain tracts upon the north. To check these they threw up a number of fortresses, either upon, or within the verge of, the hill country, of which Morlais and Castell Coch may be cited as examples.
The site of the Cymric camp was far too difficult of access to allow of the ready transport into it of provisions, or munitions of war, or of a constant and rapid communication with the chief castle at Cardiff. Lower down the scarp, though still high above the plain, the Norman engineer selected a natural platform on the limestone rock, separated from the main scarp by a natural depression, and sufficiently removed from the summit to be out of the reach of any military engines with which the Welsh were likely to be acquainted, or which they were likely to be able to bring, with their forces, against the castle. There is an easy approach to this platform from the east, which probably communicated with the old road, called Roman, and no doubt Cymric, which leads direct from Cardiff to Rubina, and close upon which is the low circular mound, which was the site of a tower of the time of Henry III., at Whitchurch, and the Celtic tumulus of Twmpath. Upon this platform was erected the fortress which is here to be described.