The Glamorgan-Gwent Archaeological Trust
Historic Environment Record

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Primary Reference Number (PRN) : 04513.0g
Trust : Glamorgan Gwent
Community : Crucorney
Unitary authority : Monmouthshire
NGR : SO3032725115
Site Type (preferred type first) : Neolithic Dyke
Status : Scheduled Monument

Summary :
Garreg Las Cross Dyke, a large stone bank (no ditch), stands across a ridge at 490m above OD.There is a worked stone, a marker of some kind. The dyke could be a Neolithic work belonging to a ritual group of monuments (Las Monument Complex, prn 08452g).

Description :
Garreg Las Cross Dyke is a large stone bank, c.8m wide, on a small depth across the west ridge of Hatterall Hill, standing at 500m above OD. The dyke takes advantage of a natural scarp (1m to 1.5 in height) and is composed of fairly large sandstone cobbles (<0.4m) with a thin covering of vegetation in places. It stands up to 2m in height. There is no discernible ditch. A slight bank up to 6m out from either side of the stone bank, suggests that the dyke may have been wider. There is a footpath situated crossing approximately the center of the earthwork. At that point is a gap which is 2m wide at the bottom and 6m wide at the top, with gentle sloping sides forming a V-shape profile. At the western end, is a stone 0.55m long by 0.33m wide with a slot in the centre (0.04m wide, 0.11m long and 0.08m in depth). This worked stone, probably a marker of some kind, distinguishes itself by its position at the very end of the dyke, but neither function nor date of this stone is clear. Also, at the western end, c.20m to the north, is a post-medieval quarry (LEWIS R 2006). The dyke could be Neolithic and so would belong to a ritual group of monuments : a henge and two satellite round barrows cairns (Las Monument Complex, prn 08452g) (Olding 2000, 91).

No palaeosoils were identified during an auger survey (E005434) and the absence of any secondary podzols, either over or beside the monument, would indicate that the dyke was raised before the development of the peat. In the other upland areas included within the present study Crampton (1966) has shown the first podzol (peat) forming in the Bronze Age with the later secondary podzols forming in the early-medieval period, which corresponds well with Olding’s (2000) hypothesis of a Neolithic provenance for the dyke and its association with the Garreg Las Monument Complex (Lewis 2006).

Sources :
Crampton, C.B. , 1966 , An interpretation of the pollen and soils in Cross-ridge Dykes of Glamorgan
Lewis, R. , 2006 , Cross Ridge Dykes of Southeast Wales: Survey and Excavation ( © Glamorgan-Gwent Archaeological Trust (GGAT))
OLDING, F. , 2000 , The Prehistoric Landscapes of the Black Mountains
01/pm record card/OS//1973/SO 32 NW 7
02/pm list///1974/County Treasures/
03/Desc Text/Cadw/ Full Management Report/2005/Copy in further information file
Cross Ridge Dykes of Southeast Wales : Survey and Exacavation

Events :
E005433 : Cross Ridge Dykes of Southeast Wales (year : 2006)
E005434 : Cross Ridge Dykes of Southeast Wales (year : 2006)

Related PRNs : 01600g, 08113g, 306448, 08957g

Compiled date : 19-08-1992

February 17, 2019, 11:44 am - HTML file produced from GGAT HER Charitable Trust Ltd. Heathfield House, Heathfield, Swansea SA1 Tel. 01792 655208; Fax 01792 474469 website:  email: Registered Charity no. 505609
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