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Llanymynech Hill


An aerial view of Llanymynech Hill from the south showing the distinctive quarry faces with the Golf Club behind. Photo 92-c-1048, © CPAT

Llanymynech Hill forms an impressive landmark, with its limestone cliffs visible for some considerable distance. The hill lies on the western edge of the Shropshire Plain overlooking the confluence of the Vyrnwy and Severn and the ramparts of the hillfort which occupies the hilltop, for much of the surviving circuit, form both a physical and political boundary between Wales and England.

The prominence of the hill, together with its natural defences, provided an ideal site for the founding of a large hillfort in the later prehistoric period and there is a belief in some quarters that this was the site of Caractacus’ last stand against the Romans in AD 51. The defences of the disused hillfort were subsequently utilised for the line of Offa’s Dyke in the early medieval period. The natural resources of the hill, principally copper, lead, zinc and limestone, have been exploited since the Iron Age, although the major focus of industrial activity shifted from the plateau top to its base around the time of the industrial revolution in the later 18th century. From the 1930s the hilltop has been occupied by Llanymynech Golf Club.

A study has recently been completed with funding from Cadw to draw together the numerous and disparate sources relating to Llanymynech Hill, as well as undertaking limited fieldwork, in an assessment of the current state of knowledge, the archaeological potential of the hill and potential management issues.

The Hillfort


The north-eastern ramparts of the hillfort survive as prominent earthworks along the 4th Fairway. Photo 3510-0009, © CPAT

Llanymynech Hill is now recognised as one of the largest hillforts in Britain with an area of about 57ha. The defences of the hillfort are best preserved on its north and north-east sides, where at least three ramparts with associated ditches can be traced. The largest surviving entrance lies on the north side, where the earthworks of the innermost rampart are inturned, but this was apparently cut off by later banks and ditches and these could be contemporary with a smaller entrance on the north-east side of the fort, where the outermost rampart also appears to be inturned. The south side of the hill appears to have been defined by a limestone escarpment, but the potential layout of the ramparts has been lost, owing largely to the effects of quarrying activity.

The interior of the hillfort presents a rolling landscape with some steep slopes, occasionally rocky where the limestone bedrock approaches the surface. Despite the elevated nature of the hill there are still sheltered areas, probably with deeper soils, which would have been suitable for settlement. These localities could have seen fairly dense occupation in the Iron Age, characterised by small four-post structures and larger roundhouses.

Explorations of the natural cave known as the Ogof and the surrounding area in the 18th century apparently revealed a number of in-situ burials, some of which were found in conjunction with material considered at that time to be of Roman date, although much of this is now missing so the cultural context is impossible to corroborate. In the mid-19th century two further skeletons were apparently found buried in trenches near the entrance to the Ogof, in association with what is described as a ‘battleaxe of mixed metal’.

In 1996 observations during the construction of a new Greenkeeper’s shed at the golf club identified a small grave containing the lower limbs of an extended juvenile burial, which has been dated to 770–370 cal. BC.

Mining and Quarrying
The hill has been heavily affected by mining and quarrying, but it is the latter which has left the greatest mark, with the larger-scale 19th-century work creating the vertical limestone cliffs to the south and south-east, which are visible from some distance. Mining on the hill was of rather longer duration and almost certainly goes back well into the prehistoric period. Although the remains are less conspicuous, they can be found in many places on the summit and sides of the hill in the form of shafts, adits and open workings, most of which are now masked with vegetation.


The entrance to Llanymynech Ogof. Photo 3510-0004, © CPAT

A range of early mine workings have been identified on Llanymynech Hill, although most attention has been paid to the Ogof, otherwise known as the Llanymynech mine. However, the earliest workings on the hill are now thought to be the series of open pits or cone-shaped hollows located in the north-western part of the hillfort, about 200m north-west of the Ogof entrance. These have a shape that implies early working methods, which concentrated initially on surface exploitation of visible mineral deposits. Later passages of similar appearance to those that constitute the Ogof have been identified in the base of at least two of these pits, implying they were reworked using underground mining techniques.

There is general acceptance that both prehistoric and Roman mining is likely to have occurred in the Ogof. Iron picks have been recovered from the workings in the past and evidence of the marks made by them or by similar tools have been identified in places. It is likely that copper ores were the most plentiful of the mineral reserves and excavations in 1981 uncovered evidence for copper smelting in crucibles immediately inside the eastern ramparts of the hillfort. This was dated to 162 cal. BC – AD cal. 53, with other activity in the period 363-119 cal. BC. The implication is clearly that the ores used were more likely to have been derived from Llanymynech than brought in from elsewhere.


An area of large open workings lies in the trees to the east of the 15th Green and may represent the remains of early mining activity. Photo 3510-0010, © CPAT

Mining seems to have undergone a hiatus following the Roman period, and it was at the end of the 12th century when the Carreghofa mine came briefly to prominence. The bishop of Salisbury, while raising the ransom money for Richard I in 1193, became aware of the discovery of silver at Llanymynech and induced the Archbishop of Canterbury to develop the mine and re-open a mint at Shrewsbury for the purpose of coining the silver.

If Llanymynech Hill was exploited later in the Middle Ages there are no written records to prove it, although mining had certainly resumed by the end of the 17th century, when gunpowder was used to re-open older workings. Later mining appears to have been rather sporadic.

Although the quarrying of limestone is likely to have a long history, large-scale exploitation only commenced in the 19th century, following the opening of the Montgomeryshire Canal and later the railway. The quarries are responsible for the scarred eastern and southern faces of the hill. Two inclines survive, one down to the village of Llanymynech, the other to the limekilns at Pant. Of the two estates with landholdings on and around the hill – the Chirk Castle and Bridgeman Estates – it was the Myddeltons of Chirk who were particularly active in leasing out their quarrying rights and this was under way by the mid-18th century; it may be that the creation of the canal at the end of the century provided the impetus for larger scale quarrying.

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