Ancient Monuments

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Craig y Llyn Mawr platform cairn and standing stone

A Scheduled Monument in Caersws (Caersŵs), Powys

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Latitude: 52.5637 / 52°33'49"N

Longitude: -3.4738 / 3°28'25"W

OS Eastings: 300198

OS Northings: 297230

OS Grid: SO001972

Mapcode National: GBR 9K.CKF4

Mapcode Global: WH68S.MT1G

Entry Name: Craig y Llyn Mawr platform cairn and standing stone

Scheduled Date: 17 August 2006

Source: Cadw

Source ID: 4259

Cadw Legacy ID: MG328

Schedule Class: Religious, Ritual and Funerary

Category: Platform Cairn

Period: Prehistoric

County: Powys

Community: Caersws (Caersŵs)

Traditional County: Montgomeryshire


The monument comprises a platform cairn and associated standing stone, probably dating from the Bronze Age (c.2300 BC - 800 BC) and situated in enclosed pasture on the SE-facing slopes of a prominent ridge to the W of Llyn Mawr. The platform cairn measures about 11m in diameter and up to 0.5m in height. There has been much disturbance to the centre of the cairn - probably the result of antiquarian investigation - although the bulk of the base of the cairn remains intact. The standing stone is situated about 110m to the SE of the cairn and measures 1.25m in height, 0.6m in width from NE to SW by 0.4m in thickness. It appears to be set within a small grass-covered stone platform or cairn.

The monument is of national importance for its potential to enhance our knowledge of prehistoric funerary and ritual practices. The monument is well preserved and is an important relic of a prehistoric funerary and ritual landscape. It retains significant archaeological potential, with a strong probability of the presence of associated archaeological features and deposits. Its position within the extensive surviving Bronze Age ritual landscape contained within this upland plateau - including several round barrows, a small cairn cemetery, stone alignments and a stone circle - further increases its importance. Indeed, its similarity to the nearby platform cairn and standing stone situated c.1km to the ESE (Scheduled Ancient Monuments MG180 and MG275 respectively) is remarkable. The proximity of two such similar associations - platform cairn and associated standing stone situated to the SE - in such similar topographic situations - the platform cairn overlooked by higher ground to the NW and situated on a terrace above the standing stone - is very unusual.

The areas scheduled comprise the remains described and areas around them within which related evidence may be expected to survive. That to the NW, containing the platform cairn, is circular and measures 24m in diameter. That to the SE, containing the standing stone, is circular and measures 8m in diameter.

Source: Cadw

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