Ancient Monuments

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Carn Pentyrch Camp

A Scheduled Monument in Llanystumdwy, Gwynedd

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Latitude: 52.9501 / 52°57'0"N

Longitude: -4.3466 / 4°20'47"W

OS Eastings: 242438

OS Northings: 341768

OS Grid: SH424417

Mapcode National: GBR 5F.L0MP

Mapcode Global: WH44C.63FQ

Entry Name: Carn Pentyrch Camp

Scheduled Date:

Source: Cadw

Source ID: 2419

Cadw Legacy ID: CN055

Schedule Class: Defence

Category: Hillfort

Period: Prehistoric

County: Gwynedd

Community: Llanystumdwy

Traditional County: Caernarfonshire


The monument comprises the remains of a small, nearly circular, heavily defended and mainly stone-built hillfort on a flattish part of the broad summit of Carn Pentyrch. It probably dates to the Iron Age period (c. 800 BC - AD 74, the Roman conquest of Wales). Hillforts are usually Iocated on hilltops and surrounded by a single or multiple earthworks of massive proportions. Hillforts must have formed symbols of power within the landscape, while their function may have had as much to do with ostentation and display as defence. The fort has a massive stone wall between 3 and 8m wide and up to 2m high with well-preserved sections of a revetted outer facing partly supported by large orthostatic stones. Where the revetment has collapsed some orthostats have been left standing or else have fallen. Surrounding the fort at a distance of approximately 15m is a second more ruinous stone wall, also with traces of revetment in places but much less wide. For the northern part of the circuit it is replaced by a massive earth bank 3m high and 14m wide with an outer ditch 5m wide and 1m deep. The third outermost defence is only present around the northern half of the summit. The ground is level for about 50m after the second defence but then slopes off gently and at this break of slope is another bank about 4m wide and up to 1.2m high, a ditch about 0.5m deep is visible on the west but becomes indistinct in the improved fields to the north. A modern dry-stone boundary surmounts the bank along most of the circuit. In the ground between the outermost bank and the second defence and at right angles to them is a line of massive stones heading to the earthen bank several of which have clearly been deliberately set upright.

The monument is of national importance for its potential to enhance our knowledge of later prehistoric defensive organisation and settlement. The site forms an important element within the wider later prehistoric context and within the surrounding landscape. The site is well preserved and retains considerable archaeological potential. There is a strong probability of the presence of evidence relating to chronology, building techniques and functional detail.

The scheduled area comprises the remains described and areas around them within which related evidence may be expected to survive.

Source: Cadw

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