The Glamorgan-Gwent Archaeological Trust
Historic Environment Record
 

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Twm Barlwm Hillfort, Risca

Primary Reference Number (PRN) : 00114g
Trust : Glamorgan Gwent
Community : Risca
Unitary authority : Caerphilly
NGR : ST2421792611
Site Type (preferred type first) : Iron Age Hillfort
Status : Scheduled Monument

Summary :
The summit of Twm Barlwm Hillfort hillfort is a flat surface of oval shape and on the highest part it is crowned with a circular artificial mound of earth and stones surrounded by a deep ditch. This mound is thought to be a Norman motte. A bronze age cairn also exists within this monument.

Description :
The summit of Twm Barlwm Hillfort hillfort is a flat surface of oval shape and on the highest part it is crowned with a circular artificial mound of earth and stones surrounded by a deep ditch. This mound is thought to be a Norman motte (00115g, MM044). Furthermore a bronze age cairn also exists within this monument (00116g).

The remainder of the hill is enclosed by a hillfort of reasonable size in a strong natural defensive position with steep to precipitous slopes on all sides. The defences consist of a fairly strong natural contour enhanced by a bank and ditch and a counterscarp bank. The interior height of the bank varies between about 0.5m and 1.5m, the exterior height between 2-3m. The ditch spans approximately 12m crest to crest and has an outer height of 1-1.5m to the top of the counterscarp bank.

The entrance has been noted as a break in the northeast entrenchments, beside the motte, however after a visit (see E001495) it is believed that this is a later break in the defences, most likely related to the construction of the motte. In the middle of the long southern edge of the enclosure, there is a large gap where the ground is undisturbed except for a small portion of the ditch and inner bank. It is probable that this is the original entrance, as due to the steepness of the scarp, the line of safe approach to the entrance is along the southwest ridge outside the fort defences, and before the natural scarp begins. The scarp meets the edge of the defences almost straight after the southeast side of the entrance, thus acting like a natural passageway entrance into the fort. The various remaining banks and ditches in the vicinity of this gap suggests the actual gap may have had complex earthworks, perhaps some sort of guard chamber attached.

The interior of the fort is grass covered, and no obvious features can be seen, although the area is under rough pasture, obscuring more ephemeral features.
The south-western quarter of the earthwork has been described as is in varying stages of completion, due to the intermittent nature of the ditches and banks in south west end of the enclosure. However the fort other than this would serve as a very good defensive area, and it seems somewhat strange to have left this so near to completion. The other alternative is that this area has been flattened, the bank pushed bank to infill the ditch, at a later date, making it possibly contemporary with the mound, if this is a later structure. Only an excavation of this area to see if there has been an unfilled ditch would answer the question. In the meantime, all possibilities are still valid. (Wiggins 2006)

In 2022 (see E008464), it was surmised that the lack of a ditch in the south-west part of the enclosure indicates that the hillfort was never completed. Whether the earthworks in this part of the site are Iron Age in date or relate to an early Neolithic causewayed enclosure underlying it, as suggested by the intermittent nature of the defences in this area, remains unclear (Logan 2022).

Sources :
, Archwilio App Submission
Logan, W. , 2022 , Twmbarlwm 2022: Archaeological Investigation
Savory H.N. , 1950 , List of Hill-Forts and Other Earthworks in Wales: II Monmouthshire , The Bulletin of the Board of Celtic Studies : XIII pt.IV : 231-238
ST. Joseph J.K.S. , 1961 , Aerial Reconnaissance in Wales , Antiquity : 35 : 263-275
Taylor, B , 2014 , Digital photograph (1); Twm Barlwm
Wiggins, H , 2006 , Prehistoric defended enclosures in Gwent ( © GGAT)
08/PM Map//Rees W/1932/S.Wales & Border in 14th C/SE Sheet
02/PM Desc Text//Savory HN/1948-50/BBCS/V13.Pt4.p234
03/PM Desc Text//Nash Williams VE/1933/Arch Camb/V88.p392
Mon p68
04/PH Desc Text//Coxe W/1801/Hist Tour in Monm/p75,plan
07/PH Desc Text//Pinnock/1825/Hist & Topog of Eng & Wales/V4.p25
09/PM Desc Text//Pickford JAF/1946/Between Mountain & Marsh/p50
06/PM Desc Text//Pugh RH/1934/Glimpses of W.Gwent/pp11-13
05/PH Desc Text///1885/Monm. & Caerleon Ant Soc/Papers re:Hist of
01/MM Record Card/OS//1957/ST 29 SW 1/
10/MM Photo/GGAT/Lewis/W/1980//
11/PM Desc Text/St. Joseph/JK/1961/Antiquity/Vol 35 p 263-275
12/MM Record Card/Newport Museum///1.2.77//
13/MM Record Card/NMW////ST29 SW/
14/MM Desc Text/CADW/1991/AM107/
15/MM Desc Text/CADW/Whittle E./1987
17/Desc Text/Cadw/Full Management Report/2007/Copy in further information file.

Events :
E001495 : Twm Barlwm (year : 2006)
E001550 : Prehistoric defended enclosures Gwent (year : 2006)
E002383 : Uplands Survey Mynydd Maen and Mynydd Henllys, Gwent SUR (year : 1997)
E008464 : Twmbarlwm, Risca (year : 2022)

Related records
National Monuments Record NPRN 307848 http://www.coflein.gov.uk/en/site/307848/details
GGAT Historic Environment Record (HER) 00115g

Compiled date : 28-01-1988


Images :



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