The Glamorgan-Gwent Archaeological Trust
Historic Environment Record

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Pen Twyn

Primary Reference Number (PRN) : 01607g
Trust : Glamorgan Gwent
Community : Crucorney
Unitary authority : Monmouthshire
NGR : SO32112303
Site Type (preferred type first) : Iron Age Hillfort
Status : Scheduled Monument

Summary :
This earthwork is situated in a commanding position at the south end of Hatterall Hill on a ridge with ground sloping away to the west and south, and with a natural scarp on the east giving panoramic views all round. The enclosure is grass and bracken covered rough grazing.

Description :
Please note that some of the sources contain information that, as yet, has not been included in this description field. This will be updated in due course.

This earthwork is situated in a commanding position at the south end of Hatterall Hill on a ridge with ground sloping away to the west and south, and with a natural scarp on the east giving panoramic views all round. The enclosure is grass and bracken covered rough grazing.
The fort comprises an oblong area enclosed by banks and ditches, with a dividing bank and ditch running east-west through the middle. While the east side is bounded by a natural scarp, the south side has a series of scarps: An inner one (2.2 high) running all the way along this side, towards the east of which there is a hollow 1m deep above it. To the south of this scarp is a berm of c18m, before another scarp of 1.5m high, the latter continuing the length of the south side, ending at the east end with a slight knoll with a hollow on its east side. Outside of this scarp is a further berm of 6m followed by a further scarp of 1.2m high, at this point the berm sometimes becomes a faint ditch. This latter scarp stops before the east end, with a hollow outside it and a bank curving round the hollow coming out from it. A further ditch lies outside of this scarp, 2-3m wide with a low bank of 0.7m high which stops short of the south end. The field wall is just inside this at the western end and on top at the eastern end.
The south-east corner of the fort has a curving entrance way flanked by a bank of 1.2m high to the east and with a knoll, c4m high on the west. The Offa's Dyke Path enters the fort here and just to the east is a small plantation of conifers. Whilst the interior of the southern half of the fort is more or less flat, a series of hollows c1m deep run along the east side near the scarp.
The middle bank and ditch separating the two halves of the fort runs in a west southwest - east northeast, with the bank to the north, 1m high to the north and 2m high to the south. The ditch to the south of this is 1.5m wide and 1m deep. A track cross the middle of the bank.
At the north end is a more massive bank, c2.5m high on the south side and 3m high on the north side, with an external ditch to the north 2m wide and 1.5m deep. Towards the west end is a gap c1m wide and 1.2m deep. The bank is lower towards the west end. To the south of the bank and ditch, within the fort is an area of bumps an hollows, some of which expose rock. Whilst the rest of the interior of the north end is more or less flat, along the west side there is a bank with an interior height of 0.7m and an exterior height of 3m. This has a farm track immediately outside it for most of its length, the track only diverging from it at its southern end. Here the bank is lower 0.4m high on the inside and 1.5m high on the outside. Outside it there is a further scarp 1.8m high. Across this bank and scarp, in the south-west corner of the fort, is cut a narrow track c1.5m wide, which once again exposes bare rock.
It is possible that the slightly smaller northern enclosure which is more rectangular is the first phase of this hillfort and the second southern part of the enclosure was a later phase. A path up the steep scarped side of Pen Twyn, may have been the entrance pathway) into the original enclosure as the pathway seems to have a slightly defensive look to it, the outer sides being banked. This is merely a suggestion at this stage however, it would explain the enormous height of the middle rampart, separating the two parts of the hillfort, as this seems to be almost more substantial than some of the ramparts to the west of the second enclosure. (Wiggins 2006)

Sources :
Wiggins, H , 2006 , Prehistoric defended enclosures in Gwent ( © GGAT)
01/Desc Text/Cadw/Full Management Report/2005/Copy in further information file

Events :
E001550 : Prehistoric defended enclosures Gwent (year : 2006)

Related PRNs : 94878

Compiled date : 02-11-1988

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