Ancient Monuments

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Hen Eglwys

A Scheduled Monument in Margam, Neath Port Talbot (Castell-nedd Port Talbot)

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Latitude: 51.5648 / 51°33'53"N

Longitude: -3.7309 / 3°43'51"W

OS Eastings: 280123

OS Northings: 186522

OS Grid: SS801865

Mapcode National: GBR H6.DL93

Mapcode Global: VH5H2.9X0T

Entry Name: Hen Eglwys

Scheduled Date: 12 May 2022

Source: Cadw

Source ID: 2870

Cadw Legacy ID: GM163

Schedule Class: Religious, Ritual and Funerary

Category: Chapel

Period: Medieval

County: Neath Port Talbot (Castell-nedd Port Talbot)

Community: Margam

Traditional County: Glamorgan


The monument comprises the remains of a late prehistoric defended enclosure (700 BC – AD 43) and medieval chapel (AD 1086 - 1536). The earlier enclosure encircles a promontory 100m above sea-level that has wide views out to the south and east. The later chapel – also known as Capel Mair – is located within the southern part of the enclosure. Item ‘A’ consists of a medieval chapel measuring 20m in length by 7.4m in width. It is of stone rubble construction and orientated on an east-west axis. There are traces of render on the exterior walls and substantial remnants of plaster on the interior. The east, west and south walls still stand to almost their full height. The west wall includes a door opening with a window above which retains some tracery. The east wall contains a window of similar but rather more elaborate design, its tracery also now incomplete. The south wall has two small windows towards the west end, a door and a larger and clearly more elaborate window toward the east end. In the south-east corner of the chapel there is a small opening for a piscina. Part of the top of the opening survives, showing an ogival trefoil design. Item ‘B’ consists of a late prehistoric defended enclosure. Measuring c. 114m east-west by c. 81m north-south, it encloses the promontory with two earthen banks and ditches on the west, north and eastern sides forming inner and outer defences. The southern side is protected by a steep drop and a possible entrance exists on the eastern side. The north-eastern section of earthworks is truncated by a modern track. In the south-eastern part of the enclosure, within the inner bank, excavation revealed a stone-lined rectangular well of unknown date (now backfilled).

The monument is of national importance for its potential to enhance our knowledge of later prehistoric defensive settlement as well as the organisation and practice of medieval Christianity. The site forms an important element within prehistoric and medieval contexts and the surrounding landscape. It is well preserved and retains considerable archaeological potential. There is a strong probability of the presence of artefactual and palaeoenvironmental remains as well as evidence relating to prehistoric and medieval chronology, layout, building techniques and functional detail.

The scheduled area comprises the remains described and an area around within which related evidence may be expected to survive. Item ‘A’ comprises the original scheduled chapel. The scheduled area has been extended to include Item ‘B’, the defended enclosure, on the basis of new information from archaeological and geophysical investigation. It centres on OS NGR 280139 186556, is roughly sub-circular in shape on plan and measures c. 127m east-west by c. 98m north-south.

Source: Cadw

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