Gwynedd Archaeological Trust
Regional Historic Environment Record

Amlwch and Parys Mountain, Landscape

Primary Reference Number (PRN) : 62421
Trust : Gwynedd
Community : Amlwch
Unitary authority : Ynys Mon
NGR : SH4393691646
Site Type (preferred type first) : MULTIPERIOD LANDSCAPE
Status : Registered Historic Landscape

Summary :
Landscape description providing an overview of the setting, geology, and history of Amlwch and Parys Mountain.

Description :
Parys Mountain (Mynydd Parys) is a low but prominent ridge, 2km long by I km wide, situated in north east Anglesey. It rises to 147m above OD and dominates prospects from the surrounding, gently undulating, surface of the Anglesey plateau. Geologically, it comprises an outcrop of Silurian shales extensively mineralised, principally with a mixture of granular quartz and pyrite (iron sulphide), chalcopyrite (copper and iron sulphide), chalocite (copper sulphide) and galena (lead sulphide). North of the ridge, the plateau surface of much older Pre-Cambrian rocks dips gently to a rocky coastline which is broken in places by small bays and inlets.
Parys Mountain was once the greatest copper mine in Wales and Britain, and the largest copper producer in Europe in the late 18th century. Its relationship with the town and port of Amlwch which sustained it make it a landscape of considerable industrial archaeological importance and the only internationally important non-ferrous mining site in Wales.
Parys Mountain itself is an immense, and visually striking, quarried landscape of the 18th and 19th centuries when it became the world's largest copper mine. lt is connected to the town and port of Amlwch which grew to serve its needs from a hamlet in 1768 to a sizeable town and harbour by the beginning ofthe 19th century. These two developments, linked by the now disused railway lines, were imposed in a very short period of time (the mining operations had all but ceased less that a century later) on an agricultural landscape with monuments and features dating back to the prehistoric period. Indeed, Mynydd Parys has yielded evidence for copper mining back in the Bronze Age, making it one of the earliest industrial extraction sites in Europe. The ores were certainly worked during Roman and later times, although the extraction sites are yet to be located with certainty.
The huge, mainly hand-dug opencast is still an awesome sight, considered by many a moonscape as the surrounding waste tips and colourful soils, impregnated with copper, lead and sulphur, have little vegetation. Remains can also be seen of dressing floors where ore was broken by hand, and kilns where it was roasted to draw off sulphur. Ocherous pools exist where copper was precipitated out of water pumped from the opencast by windmill and steam engine.
From the discovery of commercial amounts of copper on Parys Mountain in 1761 , until the early 19th century, the mines were the most productive in the world. Mining began with ad its and pits, but these soon coalesced into the two large adjacent opencasts, the Mona and Parys Mines, when miners who had been refused a renewal of their leases on their shafts and tunnels, removed supporting pillars which caused their formation. Open casting from the 1780s enabled the site to command the world copper market with an annual production of over 3000 tons, with 1500 workers being employed.
The opencasts were worked via winches on flimsy wooden cantilevered platforms projecting from the top edge of the pit. The ore, after boring and blasting, was broken up by sledge hammer and hauled up from stage to stage in baskets by a whimsey. On top, it was broken into smaller pieces, and purified by washing and by roasting for months in kilns. The opencast was pumped out successively by a windmill pump and a Pearl steam beam-engine, the housings of which remain as a prominent landmarks on the ridge. A number of surrounding dressing floors , some at one time roofed, can also still be seen. The opencasts became one of the Sublime spectacles of late 18th and early 19th centuries industrial Wales, much visited by travellers and artists in search of the contemporary aesthetic notions of the Beautiful, the Picturesque or the Sublime.
Soon after mining began, the water which collected in the workings was used in the precipitation method of recovering copper, utilising iron-filled pits that yielded a 20-30% copper sludge. The possibly unique and well-preserved remains of the stone-built precipitation pits or tanks can still be seen in many places, the best series being located on the south east of the ridge where they create a distinct lattice pattern in the present landscape.
Most of the semi-processed ore was sold or sent to smelting houses in Lancash ire and Swansea. Some of the inferior ores were smelted at Amlwch, where a rolling mill and two smelting houses had been built by 1790, and twenty furnaces were in blast at the beginning of 19th century. Preparation of ochre and sulphur occurred as subsidiary manufactures, as well as green vitriol, alum, arsenic and quartz, whilst lead was also mined from time to time. The vitriol works originally built in 1803, still dominate the headland to the west of Amlwch.
Produce was exported direct by sea, and by 1786, 35 ships were engaged in the copper trade in Amlwch. The harbour, originally a 'chasm between two rocks' was improved after an Act of Parliament in 1793, and again in 1812. Storage bins, quays and a dry dock can be seen at the adjoining port of Amlwch from which ores were shipped to the smelteries of Swansea and St Helens. As a result, Amlwch grew from a fishing hamlet to a large and flourishing town which had over 5000 inhabitants in 1801.The church was rebuilt, and Methodist and other dissenters built several chapels in the district and a private school was set up in 1814 for 'better class' children, followed in 1821 by a National School for the poor. Other buildings erected in the early 19th century included a public brewery (one of the first in North Wales), and by 1823, Amlwch had 31 inns or taverns, some of which still survive.
Production declined in the mid-19th century and, with new competition from abroad, Parys soon produced just a fraction of the British output. By 1844, the workings were 'in a great degree abandoned', and by end of century, mining had been abandoned and only precipitation continued into the early 20th century. Since 1986, renewed prospecting has occurred on the ridge for zinc and other metals, though following the slump in World zinc prices, all recently-erected new plant is now abandoned. The derelict pithead of this latest unsuccessful venture now adds to the continuing sense of sublimity originally sought by 18th and 19th centuries aesthetes on the mountain. (Cadw, 1998).

Article on the Mynydd Parys copper mines, their history and features (Cockshutt, 1965).

Sources :
Briggs, C, S , 1987 , The Parys Mountain Copper Processing Complex, Amlwch , Archaeology in Wales : vol. 27 : p. 74
Briggs, S , 1988 , Parys mountain , Archaeology in Wales : vol. 28 : p. 85
Cadw , 1998 , Landscapes of Historic Interest in Wales Part 2:1: Landscapes of Outstanding Historic Interest, Bilingual
Cockshutt, E. , 1965 , The Parys Mountain Copper Mines in the Island of Anglesey
Cooke, N. , 2014 , Rhyd-y-Groes Repower, Anglesey: Cultural Heritage Assessment. ( © Wessex Archaeology)
Greenwood, D. , 1996 , Island heritage bid

Events :
45013 : Rhyd-y-Groes Repower, Anglesey: Cultural Heritage Assessment. (year : 2014)

Related records

Compiled date : 27-01-2017


The above data are supplied by GAT in partnership with its Local Authorities (Anglesey, Conwy and Gwynedd County Councils, and Snowdonia National Park Authority), © GAT 2025 (and in part © Crown, 2025 - as indicated)
This information is supplied for the purposes of personal interest only and may not be used as part of a commercial project.

April 1, 2025, 1:27 am - HTML file produced from Gwynedd Archaeological Trust Regional HER
Gwynedd Archaeological Trust, Craig Beuno, Garth Road, Bangor, Gwynedd.  LL57 2RT
tel (01248) 352535,  fax (01248) 370925, email her@heneb.co.uk, web www.heneb.co.uk