Ancient Monuments

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Pen-Sieri Inscribed Stone

A Scheduled Monument in Aberffraw, Isle of Anglesey (Ynys Môn)

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Latitude: 53.2069 / 53°12'24"N

Longitude: -4.4951 / 4°29'42"W

OS Eastings: 233464

OS Northings: 370665

OS Grid: SH334706

Mapcode National: GBR 57.1SNG

Mapcode Global: WH42X.XNND

Entry Name: Pen-Sieri Inscribed Stone

Scheduled Date:

Source: Cadw

Source ID: 3264

Cadw Legacy ID: AN058

Schedule Class: Religious, Ritual and Funerary

Category: Inscribed stone

Period: Early Medieval

County: Isle of Anglesey (Ynys Môn)

Community: Aberffraw

Traditional County: Anglesey


The monument consists of a stone with an early-medieval memorial inscription dating to the 5th century AD. The stone measures 1.6m long and 0.4 - 0.46m square, with 'MAILIS-', (the stone of) Mail, inscribed in one vertical line. The lettering is well preserved and clear, about 8cm high and the inscription is 28cm long.

Once used as a lintel on the inner side of the window opening S of the door in the W wall of the building known as Pensieri Bach, the stone is thought to have originally stood in a field near Llanfaelog. When Pensieri Bach was demolished the stone was moved to a restored pig-sty at Trecastell c.2km further S, set vertically in the floor and secured in soft lime concrete.

The monument is of national importance for its potential to enhance our knowledge of the organisation and practice of religion and commemoration in the medieval period.

The scheduled area comprises a circular area 1m in diameter centred on the stone within the pig-sty.

Source: Cadw

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