The Glamorgan-Gwent Archaeological Trust
Historic Environment Record

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The following information is from the on-line database Archwilio


Primary Reference Number (PRN) : 02790.0w
Trust : Glamorgan Gwent
Community : Tonna
NGR : SS7868198180
Site Type (preferred type first) : Early Medieval Dyke
Legal Protection : scheduled ancient monument

Summary :
Cefn Morfydd cross ridge dyke maybe from the early-medieval period. It s well preserved apart from a few recents gaps. It is a bank and a ditch that curve gently in a north facing arch adhering to the 270m OD contour and is divided into three sections.

Description :
Cefn Morfydd cross ridge dyke is also known as the Tona Cross Dyke and is thought to belong to the early-medieval period. Located at the northern end of Mynydd Cefn Morfydd, the dyke is positioned roughly east/west on a saddle between the mountain to the south and the Gwenffrwd ridge to the north. The dyke is well preserved apart from a few recents gaps. It is a bank and a ditch that curve gently in a north facing arch adhering to the 270m OD contour.
The east end has been damaged by an industrial tramway connecting the mines at Glyncorrwg with the docks at Briton Ferry (SAM GM 447). The dyke's western end terminates near a partially destroyed earthwork enclosure, which is thought to be contemporary, although similarities in form with prehistoric domestic enclosures could also date this monument to the Iron Age.
The earthwork dyke is divided into three sections creating a continuous length from the west to a large central gap with a modern farm track through it and two smaller gaps to the east. The earthwork bank takes advantages of a natural scarp standing from 1m to 2.5m in height ; a shallow ditch is positioned to the nort of the bank visible as a slight depression and in several places a ditch is suggested on the south side of the bank by smaller but similar depression (RCAHM 1976 ; R. LEWIS 2006).

Sources :
Evans EM, 2003-04, GGAT 73 Early Medieval Ecclesiastical Sites Project
01/pm desc text/RCAHM//1976/Invent I 3/no806

Events :

Related PRNs : 94635

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