Ancient Monuments

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Gaer 594m south west of Trellech Cross

A Scheduled Monument in Trellech United (Tryleg Unedig), Monmouthshire (Sir Fynwy)

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Latitude: 51.7304 / 51°43'49"N

Longitude: -2.7356 / 2°44'8"W

OS Eastings: 349292

OS Northings: 203771

OS Grid: SO492037

Mapcode National: GBR JJ.24LL

Mapcode Global: VH876.JRNW

Entry Name: Gaer 594m SW of Trellech Cross

Scheduled Date:

Source: Cadw

Source ID: 2360

Cadw Legacy ID: MM077

Schedule Class: Defence

Category: Hillfort

Period: Prehistoric

County: Monmouthshire (Sir Fynwy)

Community: Trellech United (Tryleg Unedig)

Built-Up Area: Catbrook

Traditional County: Monmouthshire


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). The hillfort is situated on a south-facing slope below the summit of a hill, and the ground drops steeply below it on the S, E and W sides. It is roughly circular in plan, 105m in diameter, and consists of a flat interior, sloping towards the S, surrounded by a gently sloping bank and, in place, ditch. On the N side the bank is 1.2m high on the inside and 1.5m high on the outside. There is no ditch but a slight rise in the ground at the field boundary. On the E side the bank is 0.5m high on the inside and 1.8m high on the outside, with a slight ditch outside it before a steep drop below. The ditch peters out towards the S end, where the bank becomes a scarp continuous with the slope below. On the S side the scarp is 2.5m high, with a gently sloping berm c 5m wide below it which widens towards the W end. In the SW corner there is a knoll on top of the scarp. This is 1.3m high on the inside and 2.2m high on the outside and has steep sides with stones on the surface. On the lower part of its outer side there are some larger stones lying on the surface. There is a slight hollow on the SW side of the top. To the N of the knoll is a gap in the bank, 3m wide. The W side has a bank with a slight internal height and external height of 2m. Outside it is a very slight ditch and outer bank, the combined width of which is 10m. In the middle of this side there is a slight dip in the outer bank, which is most visible at its N end where it runs into the hedge at the edge of the field.

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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