Parys Mountain – in the Welsh language Mynydd Parys – is located south of Amlwch which is in north east Anglesey.
The copper from the mine at Parys Mountain dominated the world's markets during the 1780s, when the mine was allegedly the largest in the world. It was used to sheath the admiralty's wooden ships of war in order to prevent the growth of seaweed and barnacles and to prevent boring by worms. This increased the speed and maneuverability of the vessels, although it is said that Parys Mountain copper was also sold to the French for use by their fleet.
Initially ore was worked on the surface from shallow shafts, next by open-pit mining and finally underground from adits or from shafts. The ore was broken into small lumps by hand, the best ore being shipped to Lancashire or to the Lower Swansea valley in South Wales through the port of Swansea for smelting. Copper was concentrated and extracted from the remainder using kilns and furnaces on site.
It was also discovered that purer metal could be obtained efficiently, although in small amounts, by its precipitation from drainage water with scrap iron in purpose-built ponds. Associated with the mines, important chemical industries were established on the Mountain based on by-products such as ochre pigments, sulphur, vitriol and alum.
The eighteenth century miners recognised that they were following in the steps of much earlier workers, an observation that was then linked to the discovery locally of copper ingots bearing Roman inscriptions. Excavations in 2002 enabled sub-surface debris to be dated to nearly four thousand years old, (the early Bronze Age), and access has also been regained to the sealed underground workings of the Parys mine revealing evidence for this ancient mining. Parys Mountain is thus an addition to the very few sites in Britain where there is evidence for the prehistoric beginnings of the British metal mining industry.
In 1764 Charles Roe of Macclesfield was granted a 21-year lease by the Bayly family to work for copper. Rowland Pugh, a local miner, discovered the "Great Lode" on 2 March 1768 and was rewarded with a bottle of whisky and a rent-free house for his lifetime.
There is a waymarked trail around the mountain, which affords great views of Amlwch Port to the north and the nearby Trysglwyn wind farm to the south. Those wishing to go underground need to join the Parys Underground Group. The mountain has a number of examples of copper-tolerant plants and bacteria.
Since 1988, Anglesey Mining plc, which owns the western part of the mountain has discovered resources of 6,500,000 tonnes containing 10% combined zinc, lead, copper with some silver and gold and has permits and a plan to restart mining operations at 350,000 tonnes per year.
A scene in Mortal Kombat: Annihilation was filmed at Parys Mountain.