Ancient Monuments

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Gelli Diogyn Hillfort

A Scheduled Monument in Llanboidy, Carmarthenshire (Sir Gaerfyrddin)

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Latitude: 51.8624 / 51°51'44"N

Longitude: -4.6177 / 4°37'3"W

OS Eastings: 219849

OS Northings: 221442

OS Grid: SN198214

Mapcode National: GBR D1.SWSY

Mapcode Global: VH2NV.XG54

Entry Name: Gelli Diogyn Hillfort

Scheduled Date: 22 March 1999

Source: Cadw

Source ID: 867

Cadw Legacy ID: CM293

Schedule Class: Defence

Category: Hillfort

Period: Prehistoric

County: Carmarthenshire (Sir Gaerfyrddin)

Community: Llanboidy

Traditional County: Carmarthenshire


The monument comprises the remains of a hillfort, which probably dates to the Iron Age period (c. 800 BC - AD 74, the Roman conquest of Wales). Hillforts are usually Iocated on hilltops and surrounded by a single or multiple earthworks of massive proportions. Hillforts must have formed symbols of power within the landscape, while their function may have had as much to do with ostentation and display as defence. Gelli Diogyn hillfort takes the form of a large defended enclosure c. 80m in diameter. The central sub-circular shaped enclosure is defined by at least two lines of bank and ditch defences, the banks up to 0.6m high. There is a single elaborated entrance defined by a corridor-like approach with banks and ditches extending outwards in the form of antennae. The overall enclosure with its outworks has dimensions in excess of 230m x 160m. 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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