Glendalough Mines, Co. Wicklow (OS 095965)
Interestingly, the footpath from the village car park to the head of the valley is marked as the Miners Walk to the Cornish Village. This walk takes about 30 minutes and the site is found just beyond the upper lake. Glendalough means "glen of the two lakes" and the area has long been regarded as one of the most picturesque settings in Ireland. A circular walk can be made to take in both the Glendalough and Glendasan mines and this will take about 2 hours.
Today, the monastic round tower and the shores of the lakes make a popular stopping place on the way to the Wicklow gap but few visitors make the 3km trek beyond the lake to the abandoned mine workings beside the Glenealo River. Two hundred years ago, the upper reaches of the valley were genuinely remote and one of the mines became known as "Van Diemen's" because it seemed so far from civilisation!
The granite rocks of the glacial valley contain quartz veins with silver, lead and zinc mineralisation. The other major rock type is schist, formed when the molten granite metamorphosed the older sedimentary rocks. Glendalough and the next valley, Glendasan, were extensively mined between 1800 and 1920, employing around 2,000 miners at the peak of production. Some levels are reputed to stretch the 2km from one valley to the other.
The eye-catching white spoil heaps can be seen as soon as the walker emerges from the lakeside wood. What is less expected is an almost intact roller crusher at the foot of the dumps, inscribed "J.MILLS FOUNDRY LLANIDLOES NORTH WALES". The gently rusting relic rests on concrete foundations beside other relatively modern building remains and was probably used for re-working the dumps. The cast iron rolls have replaceable steel tires which are worn into shallow grooves and a nest of powerful springs held the rollers together as the rock passed through. The ore hopper has been removed but the iron sides still lie near the crusher. The brass-work of the bearings is gone but the gears and shafts are in good condition. There are building remains nearby and there is a hidden flooded adit just behind the buildings. Two further adits can be reached by scrambling up the loose scree, these were both explored and were found to have collapsed.
The tips above the crusher are well-graded and are obviously the work of some other earlier crushing plant higher up. At this point, the locations of many of the mines levels can be seen high up amongst the screes on the northern valley side, marked with large linear spoil dumps. A level was explored here by the Club which went a reasonable distance, traversing a ledge with possible descent to lower workings and pushing through one constriction until blocked.
The main site of Glendalough mine is soon reached. South of the path is an area of ground distinguished by a kerb of stones, with substantial retaining walls beside the river. There are the stumps of wooden posts inclined together, which probably supported a trestle bridge. To the north is a well-preserved stone-built ore hopper or bouse-stead, with smoothly cobbled interior surfaces and a flanged cast-iron pipe emerging from the ground.
A little further upstream are the stone walls of four single-storey buildings. These may be miners' dwellings but they are very close to another building, which is probably the earlier crusher house. This has thick stone walls two storeys high with the usual collection of enigmatic openings for machine shafts and bearings. One speculation is that this contained a waterwheel-powered ore crusher of a much earlier date than the Mills machine.
It could well have been another roll crusher but using a weight on a lever arm to hold the rolls together and a raff wheel to return partly crushed ore to the top of the mill. It is now on an island in the Glenealo river but the course of the stream may have changed since it was in use. Between this building and the river is a smoothly cobbled floor, which may have been used for hand bucking of ore with hammers. Below the crusher house, there is an area with fine slimes and wooden launders which was presumably a dressing floor.
The zig zag footpath by the river can be followed to the top of the hill where
the spoil tips of Van Dieman's Lode Mines can be found, with various remains
of tracks, inclines, barracks, collapsed adits and spoil tips.
See Cole's Memoir pages 84, 110, 112.
Added to MHTI WebSite March 11th, 2001
Last Revised May 11th, 2001