Ancient Monuments

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Castell Gwyn

A Scheduled Monument in Llandissilio West (Gorllewin Llandysilio), Pembrokeshire (Sir Benfro)

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Latitude: 51.8621 / 51°51'43"N

Longitude: -4.7461 / 4°44'45"W

OS Eastings: 211008

OS Northings: 221739

OS Grid: SN110217

Mapcode National: GBR CW.STP5

Mapcode Global: VH2NS.PG9B

Entry Name: Castell Gwyn

Scheduled Date: 23 November 1950

Source: Cadw

Source ID: 2681

Cadw Legacy ID: PE225

Schedule Class: Defence

Category: Hillfort

Period: Prehistoric

County: Pembrokeshire (Sir Benfro)

Community: Llandissilio West (Gorllewin Llandysilio)

Traditional County: Pembrokeshire


The monument comprises the remains of an earthwork/stone-built enclosure, which probably dates to the Iron Age period (c. 800 BC - AD 43) and is located on a west-facing ridge top spur above the Eastern Cleddau valley. It comprises an oval enclosure of internal dimensions c.55m north to south by c. 30m east to west which is defended by a series of ramparts. An inner bank and ditch run around the complete circuit, a second bank and ditch extends for c. 100m around the south side and a third bank and ditch runs close to the others on the south but otherwise diverges to each side to form a larger horseshoe-shaped enclosure of c. 125m north to south by c. 100m east to west which extends northwards to rest upon steep natural scarps above the valley. On the west side of the horseshoe-shaped enclosure the defences are well preserved, with the bank standing up to 2m above the bottom of the ditch. There is a well-defined counterscarp bank on this side. The defences on the eastern side are overlain by a hedge-bank. Entrance to the inner enclosure appears to be through simple southwest-facing gaps through the sequence of ramparts.

The monument is of national importance for its potential to enhance our knowledge of later prehistoric defensive organisation and settlement. The site forms an important element within the wider later prehistoric context and within the surrounding landscape. The site is well preserved and retains considerable archaeological potential. There is a strong probability of the presence of evidence relating to chronology, building techniques and functional detail.

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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