Ancient Monuments

History on the Ground

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Castell Grogwynion

A Scheduled Monument in Trawsgoed, Ceredigion

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Latitude: 52.3356 / 52°20'8"N

Longitude: -3.8784 / 3°52'42"W

OS Eastings: 272114

OS Northings: 272496

OS Grid: SN721724

Mapcode National: GBR 91.TV14

Mapcode Global: VH4FV.QKJD

Entry Name: Castell Grogwynion

Scheduled Date:

Source: Cadw

Source ID: 3414

Cadw Legacy ID: CD012

Schedule Class: Defence

Category: Hillfort

Period: Prehistoric

County: Ceredigion

Community: Trawsgoed

Traditional County: Cardiganshire


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 located 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. Castell Grogwynion sits on a knoll overlooking the Ystwyth valley and is broadly rectangular in plan, measuring c.170m east-west by c.100m north-south. The fort has one main gate at the north-east point, with a complex arrangement to the entry. However, there are at least two further gateways on the main northern defensive circuit suggesting a long and complex history to the development of the fort, perhaps beginning with a smaller hillfort enclosing the highest point at the west end, with subsequent enlargement onto the slopes below and to the east. The interior falls c.29 metres from the summit of the western outcrop to the approaches of north-east gateway. The interior of the fort as it survives today is arranged in a series of three or possibly four ‘steps’ or compartments, with the main gate positioned at the lowest (north-east) point and the visitor progressing upwards (westwards) through the fort. On the last terrace below the western outcrop are the remains of three denuded house platforms.

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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