Ancient Monuments

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Cothi Roman Aqueduct

A Scheduled Monument in Cynwyl Gaeo, Carmarthenshire (Sir Gaerfyrddin)

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Latitude: 52.0707 / 52°4'14"N

Longitude: -3.9111 / 3°54'39"W

OS Eastings: 269107

OS Northings: 243089

OS Grid: SN691430

Mapcode National: GBR DZ.CQJ1

Mapcode Global: VH4H6.566Z

Entry Name: Cothi Roman Aqueduct

Scheduled Date:

Source: Cadw

Source ID: 2160

Cadw Legacy ID: CM213

Schedule Class: Water Supply and Drainage

Category: Aqueduct

Period: Roman

County: Carmarthenshire (Sir Gaerfyrddin)

Community: Cynwyl Gaeo

Traditional County: Carmarthenshire


The monument consists of the remains of a water channel, dating to the Roman period.

It is believed to have been constructed in conjunction with the Roman exploitation of the gold mines at Dolaucothi, probably in the later 1st and early 2nd centuries AD. It lies some 50m vertically above the main Dolaucothi Aqueduct (CM200) and is presumed to run for a total of over 5 kilometres, depending on its exact source in a side valley at either Cwm Dâr or Pen-twyn, down the southern flank of the Cothi valley to the gold mines near the village of Pumsaint, where it may have fed a tank above the Cwmhenog opencast. The channel is only definitely known around the bluffs of Banc Maes-yr-Haidd and Banc Llwynceiliog, where it hugs the contour of the hillside. Some parts of its course were probably carried on or supported by timber structures which do not survive. Nowhere is it possible to calculate the original width and depth of the channel. This is part of a network of leats serving the Dolaucothi mine, and an important demonstration of the sophistication of water management by Roman engineers.

The monument is of national importance for its potential to enhance our knowledge of Roman structural engineering and mining technology. The scheduled sections of the monument are generally well-preserved and an important relic of their Roman construction. They retain significant archaeological potential, with a strong probability of the presence of both structural evidence and intact associated deposits.

The scheduled area comprises the remains described and areas around them within which related evidence may be expected to survive. The scheduled area comprises four sections A-D, all strips 15m wide: A Extends from SN 6974 4328 to SN 6945 4328 B Extends from SN 6943 4335 to SN 6902 4325 C Extends from SN 6896 4304 to SN 6897 4297 D Extends from SN 6906 4279 to SN 6848 4277

Source: Cadw

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