GGAT00633g

The Glamorgan-Gwent Archaeological Trust
Historic Environment Record

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Corn Mill, Llantarnam

Primary Reference Number (PRN) : 00633g
Trust : Glamorgan Gwent
Community : Llantarnam
Unitary authority : Torfaen
NGR : ST3089493109
Site Type (preferred type first) : Modern Barn / Medieval Mill

Summary :
Visual inspection of the Mill Barn suggested that the present structure may contain the remains of an earlier structure which was possibly a mill and elements of the mill are thought to be of 19th century in date. From 1907 the mill was converted to a hall for gatherings.

Two watercourses supplied the mill of which there are some traces still visible.

The first mention of a watermill at Llantarnum is in the Ministers accounts for 1535-6. Before this, a grinding mill is mentioned. Due to a watermill being recorded at from the dissolution of the Abbey until 1888, with no suggestions that its position had been changed it is probable that the position of the last mill i.e Mill Barn was the site of the medieval monastic mill.

Description :
During the course of fieldwork, visual inspection of the Mill Barn suggested that the present structure may contain the remains of an earlier structure which was possibly a mill. Elements of the building are thought to be of 19th century in date and were probably associated with a watermill and a mill building is shown in this position on the tithe map of 1840. In 1888 it is recorded as a water corn mill of 4 floors with 2 breast wheels not worked (Llantarnam deeds). However in 1907 it had been altered to its present form as a hall for gatherings and the mill force supplied the electricity.

The tithe map (1840) and the first edition of the ordnance survey map show that water to power the mill was supplied by two watercourses. The first of these left the Afon Lwyd to the north of Court Farm (NGR ST 3028 9421), followed the course of the present Llantarnam road and continued along the northern side of Abbey Lane, a distance of 1.36km. The only evidence of this remaining can be seen in the abandoned nursery to the north of Abbey Lane, where a bank 32m long and c.2m high is situated.

The second watercourse left the Dowlais Brook at Court Wood (ST2992 9352) and proceeded to the south of Greenhouse Public House and then along the southern boundary of the abandoned nurseries to the mill, a distance of 1.31km. The course is preserved by a modern drain from the Brook to the Greenhouse Public House and from there on has become a public footpath. The two watercourses met at ST 30889309 where a complicated system of sluices controlled the flow of water.

The mill is positioned on a steep escarpment allowing a fast flowing race to be provided. A spillway looped south of the mill and the tail-race ran west to the Afon Llwyd, joining the river at ST 3144 9318. The line of the rail-race can still be seen as a linear depression alongside the present fenceline.

The construction of these large watercourses, from two separate sources would have required a lot of manpower and would imply that both sources of water were under control of the same landowner.

The first mention of a watermill at Llantarnum is in the Ministers accounts for 1535-6. Before this, a grinding mill is mentioned. Due to a watermill being recorded at from the dissolution of the Abbey until 1888, with no suggestions that its position had been changed it is probable that the position of the last mill i.e Mill Barn was the site of the medieval monastic mill.

This building was recorded before demolition and part of its site was then excavated. It measured 16.7m long x 6.4m wide and was aligned northwest-southeast. Excavation revealed it to be a multi-phased structure which had undergone fundamental changes in the latter part of its history when it was converted from a water mill into a meeting house. For much of its history the mill building housed both a fulling (northwest end) and a corn mill (southeast end). Each mill had its own water supply and wheel.
Much of the dating of the building was based on analysis of the mortar. The most complete construction sequence was recovered from the northwest end of the building, in all, 5 phases of activity were identified.

Phase 1: Late Medieval - early post-medieval.
Fulling Mill.
Part of the original walls were still standing: these were the southwest wall and the northwest gable wall. Excavation revealed the presence of part of the original northeast wall and the supporting wall for the end of the main axle and the tappet-wheel.
The southwest wall and the northwest gable wall which were of one build, were bonded by a soft mortar with a low lime content indicating a 15th-17th century date. They were constructed from two sins of split river-boulders with a sandstone rubble core. The two walls stood to the full height of the building. The southwest wall had traces of a central doorway which was probably original and there were also two windows 1m square in this wall but these may not have been original.
Two short lengths of the original northeast wall were uncovered (298 and 299). Wall 298 was 0.7m long and 0.39m high and wall 299 was 1m in length and 0.51m high. Parallel to the northwest gable wall were two further walls (223 and 256), one 1.7m away; 4.2m long x 0.45m wide and the other 1.94m away 3.9m long x 0.4m wide. These walls supported the end of the axle shaft and tappet-wheel.
Corn Mill. At the southeast end of the building was a section section of northeast-southwest wall, 1.5m long and 0.58m wide. This wall supported the end of the axle shaft and the foot of the vertical shaft and also formed the inner wall of the pit for the pit-wheel.

Phase 2: Early Eighteenth Century.
The original northeast wall was demolished and replaced by a new one on the same line. A curved wall was built across the northeast end of the gap at the northwest end of the building. A new wall was also constructed at the southeast end of the building.

Phase 3: It was during this phase that a number of large scale alterations and reconstructions took place. These included the addition of an extension to the northwest end, the blocking of the gap (236) and the construction of a water culvert in order to channel water towards the tail-race at the northwest end of the building. One result of these changes was to block the fulling pit.

Water management system phases 1-3: The water system for the mill consisted of a mill-pond fed by two leats. A series of sluices controlled the flow of water to the mill. From the pond, the water was directed under Abbey Lane and either side of the mill to the two wheels, possibly through stone-built culverts.

Phase 4 (late 19th-early 20th century). This is the period where the mill was converted into a meeting house. Very few alterations were required: they consisted of the blocking of the old windows and other openings and the insertion of new decorative windows and doors in keeping with its new use. A new wall was built at the northwest end of the building to block the water culvert. Another wall was constructed and a metal water pipe inserted at the southeast end of the building. The fulling pit and the pit-wheel were filled in.
The mill pond and the leat that passed the Greenhouse public house survived into this phase. It is likely that the other elements were decommissioned during the reorganization of the system to supply water to the electricity generator.

Phase 5: 20th century. During this period the alterations to the building were largely connected with agriculture and included the blocking of a window in the southeast wall with breeze blocks and brick and the erection of barns against the southwest and northeast walls. During the 1960's the extension was converted into a grain drier by the construction of a concrete hopper and the destruction of part of the southwest wall to allow grain to be tipped into the drier. The overflow was filled with very modern domestic farm refuse. The water culvert was also damaged during this period by the insertion of a cess-pit.

Sources :
Maylan, N. , 1992 , Trial Excavations at Llantarnam Village, Gwent. (

© GGAT)

Events :
E003755 : Excavations at Llantarnam Village. (year : 1993)
E003737 : Evaluation at Llantarnam Village (year : 1992)
E008475 : Former British Ironworks, Talywain, Aberyschan, Torfaen (year : 2022)

Related records
GGAT Historic Environment Record (HER) 00624g
GGAT Historic Environment Record (HER) 12213g
National Monuments Record NPRN 413683 https://coflein.gov.uk/en/site/413683/details/llanfihangel-llantarnam-mill

Compiled date : 02-03-1988

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