Ancient Monuments

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St Seiriol's Well, Penmon

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

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Latitude: 53.3064 / 53°18'22"N

Longitude: -4.0566 / 4°3'23"W

OS Eastings: 263060

OS Northings: 380798

OS Grid: SH630807

Mapcode National: GBR 0Z36.KG

Mapcode Global: WH53W.N5H3

Entry Name: St Seiriol's Well, Penmon

Scheduled Date:

Source: Cadw

Source ID: 3265

Cadw Legacy ID: AN062

Schedule Class: Religious, Ritual and Funerary

Category: Holy Well

Period: Early Medieval

County: Isle of Anglesey (Ynys Môn)

Community: Llangoed

Traditional County: Anglesey


The monument comprises the remains of an Early Medieval holy well and a cell 25m north-north-east of Penmon church. It is probable that these remains marked the settlement of St Seiriol, the founder of the religious community at Penmon.

There is a double structure which encloses the well, this represents the chancel and nave of a chapel. The adjoining oval structure may have been St Seiriol's dwelling. The well is enclosed by a small rectangular structure, 2m by 1.8m, with an open forecourt 2.5m square, from which it is entered. The structure is built against a vertical rock face which forms one side; the lower parts of the walls, showing a batter on the east side, are older than the upper portions and the roof, which date probably from the 18th century and are partly of brick. Internally, a stone bench runs round three sides, and in the north and east walls are recesses, one of which is partly blocked by a slate slab with a coronet above the initials RBB and the date 1710. The floor is paved. The forecourt is surrounded by a low stone wall, along the inner face of which is a stone bench. Adjoining the forecourt on the south-west and filling the space between it and the rock face is a recessed platform about 1.5m above courtyard level. Set in this are the stone foundations of an oval building 3.5m by 3.3m with a southern entrance.

The monument is of national importance for its potential to enhance our knowledge of the organisation and practice of Christianity. It retains significant archaeological potential, with a strong probability of the presence of associated archaeological features and deposits. A holy well may be 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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