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Cof Cymru: National Historic Assets of Wales · Wales

Carreg Maen Taro

Blaenavon, Torfaen, Wales

The record

Designation
Listed building, Grade II
Broad class
Civil
Date of designation
9 February 1995
Town
Garn-yr-Erw
Community
Blaenavon
Unitary authority
Torfaen
Country
Wales
Coordinates
51.79532, -3.10589
Cadw reference
15306

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David Rumsey Map Collection, Stanford Libraries

Shown on 5 historical map sheets, the earliest the 1636 "Cornubia : Devonia, Somersetus, Dorcestria, Wiltonia, Glocestria ..." (David Rumsey Map Collection, Stanford Libraries).

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This record in Cadw's own full report ↗

Cadw's description

Located at the top of the mountain 1.5 km north of Garn-yr-Erw, at the border of the Blaenavon, Llanfoist Fawr and Llanelly communities.

A roughly hewn standing stone 1.7m high marked with the letters 'B' and 'M' and surrounded by a spread of smaller stones. It is traditionally reputed to mark the site of an ancient battle. The date of erection is uncertain. However the stone is situated on the line of the former boundary between the counties of Brecknockshire and Monmouthshire, to which the letters refer. The 'M' is carved on the south-east side and the 'B' on the north. The letters are in a primitive serifed Roman style, suggesting they were probably carved in the eighteenth or early nineteenth century. The stone also marks the geological fault known by the name, which can be translated as'stone of rock striking', meaning perhaps that the standing stone was where surface rock was met at the fault.

Listed as an unusual surviving county boundary stone.

Nearby in the register

Other entries of the same register within about three miles of this one, by straight line.

Designated Historic Asset GIS Data, The Welsh Historic Environment Service (Cadw), 2026-09-07, licensed under the Open Government Licence http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/ Cadw, the Welsh Historic Environment Service · Open Government Licence v3.0
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