Ancient Monuments

History on the Ground

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Maen Serth, Esgair Dderw

A Scheduled Monument in Rhayader (Rhaeadr Gwy), Powys

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Latitude: 52.3169 / 52°19'0"N

Longitude: -3.552 / 3°33'7"W

OS Eastings: 294306

OS Northings: 269886

OS Grid: SN943698

Mapcode National: GBR 9G.W445

Mapcode Global: VH5CP.D126

Entry Name: Maen Serth, Esgair Dderw

Scheduled Date:

Source: Cadw

Source ID: 1923

Cadw Legacy ID: RD043

Schedule Class: Religious, Ritual and Funerary

Category: Standing stone

Period: Medieval

County: Powys

Community: Rhayader (Rhaeadr Gwy)

Traditional County: Radnorshire


The monument comprises the remains of a standing stone, which may date originally to the Bronze Age (c. 2300 - 800 BC) but which bears an inscribed cross of early-medieval type. The stone is also known as Carn Bica. At some stage during the 20th century it was reset in concrete. It now stands 2.1m high and is 0.53m wide and 0.18m thick, though part of the top is broken away. It is aligned north to south, with an incised cross on its east face, the centre of which is 1.54m above the base. The upper and right-hand parts of the cross are missing, while the lower is 0.12m long and the left-hand 0.15m long. The cross was traditionally associated with the murder of Einion Clud, a local Welsh Chieftain, in 1177, although it has been dated rather earlier on stylistic grounds, to the 7th to 9th centuries AD.

The monument is of national importance for its potential to enhance our knowledge of prehistoric burial and ritual practices, and of the organisation and practice of medieval Christianity. It is an important feature in the landscape and retains significant archaeological potential. There is a strong probability of the presence of intact ritual deposits, together with environmental and structural evidence. Standing stones are often part of a larger cluster of monuments and their importance can further enhanced by their group value.

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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