Ancient Monuments

History on the Ground

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Clawdd Du

A Scheduled Monument in Monmouth (Trefynwy), Monmouthshire (Sir Fynwy)

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Latitude: 51.8066 / 51°48'23"N

Longitude: -2.7214 / 2°43'17"W

OS Eastings: 350356

OS Northings: 212246

OS Grid: SO503122

Mapcode National: GBR FK.XCLK

Mapcode Global: VH86T.SV5D

Entry Name: Clawdd Du

Scheduled Date:

Source: Cadw

Source ID: 3674

Cadw Legacy ID: MM036

Schedule Class: Defence

Category: Town defences

Period: Medieval

County: Monmouthshire (Sir Fynwy)

Community: Monmouth (Trefynwy)

Built-Up Area: Monmouth

Traditional County: Monmouthshire


The monument comprises the remains of a stretch of the medieval town defences. It consists of a long, curved, steep-sided ditch, 3m to 4m wide at the base and 2m deep, orientated roughly NW/SE to the W of the river Monnow. The ditch, which records show was also called the Black Dyke, was built to provide protection for the suburb of Overmonnow, which was an important iron and wool working centre during the medieval period. Originally there would have been a large bank on the inner (E) side of the ditch, possibly surmounted by a wooden palisade, but the ditch has been flattened. A stone bridge crosses the N end of the ditch, this is medieval in date and would have carried a road across the ditch towards the Monnow Bridge (MM008).

The monument is of national importance for its potential to enhance our knowledge of medieval defensive organisation and of the growth of towns. The monument forms an important element within the wider medieval context and the structure itself may be expected to contain archaeological information in regard 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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