Glendalough is one of Ireland’s most famous heritage sites. Over ½ million visitors come here each year to see the monastic remains, view the valley or take walks on the hills. Few of these visitors realise that Glendalough and the nearby Glendasan valleys were the most important sites for lead mining in Ireland.
Lead has been in demand for thousands of years. The Romans used it plumbing (which takes its name from the latin name for lead – Plumbum) and it was used for roofing in medieval times. In more recent times lead has been used as a pigment, for solders and for batteries. The main lead mineral in Wicklow is Galena (PbS) which often contains small amounts of silver which could also economically be extracted. At Silvermines in Co. Tipperary there were active lead mines in the 13th century, but the first reference to lead mining in Wicklow was in the early 19th century. Lead was first discovered in Glendasan and later the veins were followed through the mountainside to the adjacent valley of Glendalough.
There were three distinct phases to the mining at Glendsan/Glendalough. The first phase was associated with the development of the mines by the Mining Company of Ireland from 1825 until 1890. The second phase was a re-working of the mines and tips by the local Wynne family from 1890 to 1925. A modern operation between 1948 and 1957 (third phase) concentrated on the development of new workings at depths below old workings in the Glendasan valley.
At the Glendasan and Glendalough lead mines are remains of mining landscape which it is hoped can be preserved. There is a wealth of mining heritage remains; including buildings; waterwheel pits, leats and dressing floors. It is intended that mining trails and interpretation boards are developed for the sites. Glendalough and Glendasan valleys are now under the care of the Wicklow Mountains National Park, which cares for the natural flora and fauna and surviving built heritage of the area.