The Glamorgan-Gwent Archaeological Trust Ltd.

Merthyr Mawr, Kenfig and Margam Burrows

Historical Processes, Themes and Background


The solid geology of the general area is varied: the cliff line around Sker is mainly characterised by an exposure of Triassic marls, to the south of Ffynnon Wen Rocks and around Porthcawl and Ogmore Down limestone predominates, interspersed with marls at Black Rock, Ogmore and Ogmore-by-Sea. The solid geology is largely masked inland by a capping of glacial drift deposits of the Pleistocene period, approximately 18,000 years ago, exposed as boulder clay around Kenfig, Maudlam and inland of Sker towards Parc Newydd farm. The principle glacial collecting point in South Wales was the Carmarthenshire Fans and the Brecon Beacons, the northern face of which was the source of numerous corrie glaciers. The Pennant escarpment and Craig-y-Llyn was the only barrier effectively to deflect the main Fans-Beacons ice-flow and created an icecap of its own. It was this force of ice, which modified the valleys of the area, including the Afan, Llynfi, Cynffig (Kenfig), and Ogwr (Ogmore) Valleys (George, N 1970 126-7). Extensive wind blown dune formations have masked the coastal embayments at Margam, Kenfig and Merthyr Mawr Burrows in addition to some of the eroded flanks of the higher ridges of the area, specifically at Cwm y Gaer and Ogmore Down, since the medieval period (BRG 1975; GS 1972). The nature of the encroaching dune formations is chiefly characterised by fairly deep calcareous and non-calcareous sandy soils, with some waterlogging in the hollows, or slacks within the formation. The former course of the River Kenfig, south east of Kenfig Pool is identifiable as an area of alluvium.

The natural process of coastal erosion and be-sandment has had an overriding impact on the Merthyr Mawr, Kenfig and Margam Burrows Merthyr Mawr historic landscape areas. Accumulations of wind blown sand have formed considerable areas of littoral dunes at a number of points along the South Wales coast, with their distribution primarily controlled by coastal topography and by the prevailing westerly winds. They are commonly found in bays; their extent limited by the size of the bay and the relief of the hinterland. Historical evidence indicates that the processes of be-sandment were very active in the later medieval period, during the 13th to 15th centuries, with a deterioration of climate and a noticeable increase in be-sanding as the result of storms, higher rainfall and abnormal tides, all occurring in combination. These conditions led to the erosion of coastal sand dunes and the movement of material inland. Similar processes had a major impact on coastal landscapes elsewhere in Wales, such as at Llanddwyn or Newborough Warren on Anglesey, where the lands associated with the 12th/13th century Llys/maerdref settlement of Rhosyr were affected.

The extensive dunes of Kenfig Burrows conceal buried remains dating from the prehistoric to early post-medieval period, while the pre-Norman settlement of the area is illusive, and largely related to finds. The dunes of Kenfig and Margam Burrows lie about 7km north west of Merthyr Mawr, on the coastal plain between the sea and Margam Mountain to the north, and they have retained their distinctive and striking appearance despite having been bisected by modern rail and motorway communication systems on their eastern fringes. They are much lower, but more extensive than the Merthyr Mawr dunes. The Warren at Merthyr Mawr (HLCA 013) is located on the north west side of the estuary of the River Ogmore. The dune system is much higher than at Kenfig, reaching a height of 80m OD, and tending to dominate prospects of the estuary and the immediate hinterland around Merthyr Mawr, which, as defined here, includes Ogmore Castle on the opposite bank of the estuary to the dunes.

The relatively small historic landscape areas of Merthyr Mawr, Kenfig and Margam Burrows comprise two discrete areas of dunes situated in the western part of the Glamorgan coast. They present the supreme examples in South Wales of these natural and uncontrollable forces, and the significant impact they had on earlier societies. Inevitably, two landscapes are represented, the one at Margam and Kenfig as the be-sanded landscape that essentially derived from adverse weather conditions and tidal phenomena in the Middle Ages and perhaps earlier, and the other at Merthyr Mawr as a generally more ancient landscape with archaeological sites completely buried by these natural forces; the specific landscape themes are dealt with below.

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Settlement and defence

The themes of settlement and defence are strongly linked from the medieval period and have therefore been treated jointly below. During the post-medieval period landownership the area was held largely by three main estates: Margam, the main landholder, Merthyr Mawr, and Dunraven. The main settlements continued to develop along agricultural lines, and associated agri-industrial activities centred on the settlements with mills located at Kenfig, Llanmihangel, Merthyr Mawr and Ogmore. Many of the post-medieval settlements are considered to have medieval precursors many referred to in the Margam Charters of the 13th and 14th centuries.

The earliest evidence of human settlement in the area is represented by a small mixed assemblage of flint tools dating to the Mesolithic (10000-4400BC), Neolithic (4400-2300BC), and early Bronze Age (2300-800BC) periods with only slightly larger concentrations of material evidence, so far located beyond the historic landscape boundaries; mesolithic material is evident west of Blaen Rhondda, while neolithic evidence is largely restricted to the coastal fringe around Baglan Bay and Margam Beach, and includes a thin-butted stone axe of late Neolithic date (Greaves-Brown; Evans 1982). This evidence of human activity is thought to represent temporary hunting camps, occupied by hunter-gatherer groups as part of a seasonal migration pattern between the coastal lowlands and the upland Blaenau.

There is significant evidence for activity in the adjacent upland areas during the Bronze Age; however this is predominantly related to upland funerary monuments. The whereabouts of settlement is largely based on stray finds of flint tools, the distribution being similar to earlier periods. The effect of human activity on the natural vegetation of the area is clear from pollen analysis carried out in the locality; this is at its height at the end of the Bronze Age, and it is perhaps no surprise that the first major impact of human settlement on the physical environment of the area dates to this and the following period, the Iron Age.

Over the last century, the dunes at Merthyr Mawr (HLCA 013) have produced a diverse range of archaeological material indicating occupation and activity from the Mesolithic period to the recent past, through the recurrent exposure of buried archaeological features and surfaces caused by the movement of sand. The archaeological potential of the dunes at Merthyr Mawr is extremely high, since records of finds suggest occupation sites of the Mesolithic, Neolithic, early Bronze Age (represented by cist graves and tumuli) and Iron Age (with evidence of metalworking).

The extent of early medieval settlement in the area is unknown; however it is likely that some measure of continuity of native settlement carried over from the late prehistoric/Roman period. No definite settlement sites of the early medieval period are known for the area; re-occupation, or even continuity of use, of late-prehistoric settlement and enclosures, into the early medieval period and conversely from the period into the medieval period proper, might explain the paucity of settlement sites ascribed to the early medieval period.

In historic times, medieval occupation is attested by finds of pottery, walling, shell middens, cultivation ridges, roads, boundary stones, and a windmill of possible 15th century date sited on top of the dunes. Movement of the dunes continues and Candleston Castle (SAM Gm 95; HLCA 014), a ruined, small, fortified manor house originally built mainly in the late 14th century, was occupied into the 19th century, but now stands up against the eastern edge of the dunes with its land completely buried in sand.

In the surrounding landscape relict features are also characteristic with unexcavated sites, such as the small univallate hilltop camp (SAM Gm 238; HLCA 012) at Chapel Hill, Merthyr Mawr, and the promontory fort (SAM Gm 466) on Fleming's Down SE of Ogmore indicating the whereabouts of late prehistoric (Iron Age) occupation; both sites might equally reveal early medieval use, however.

Historically and archaeologically, the Kenfig area is also rich in the evidence of the past, notably the be-sanded castle and fortified borough of Kenfig (SAM Gm 42). Although Kenfig is considered to be Norman foundation, other archaeological finds of the prehistoric, Roman and Dark Age periods from the immediate area indicate that the site was favoured for settlement from an early date.

References to pre-Norman settlement at Kenfig, such as that in the now partly discredited Gwentian Brut to settlement at Kenfig existing during the 9th century, and traditions that in 1080 Iestyn ap Gwrgan, the last native ruler of Morgannwg, had a castle (location as yet unknown) at Kenfig are compelling. These traditions might indicate the area was an administrative focus prior to the arrival of the Normans; concentrations of Roman and early medieval finds support this, while the proximity of the area to known lines of Roman communication and the location of the site close to formerly navigable/tidal limits on the River Kenfig (its course later diverted from its route via Kenfig Pool through sand incursion), vital for trade and supply, would have been important considerations in administrative or high status settlement location, a factor not lost on the later location of the Norman Castle itself. The church of Maudlam, dedicated to St Mary Magdalane and first mentioned in mid-13th century documents, has a sub-rectangular churchyard, possibly indicating an early origin, with its original early medieval dedication now lost.

The strategic and exposed position of the castle borough as the western outpost of the Lords of Glamorgan in the 12th century accounts for its exceptionally full documentary record. Between 1167 and 1321 the Welsh, now confined to the nearby uplands of Margam Mountain, made no less than eight recorded attacks on Kenfig. Today's landscape reflects much of the conflict between these warring factions, the one conquering and enjoying the rich lowlands, the other ousted and confined by military might to the hills within viewing distance of Kenfig's walls.

Both Kenfig Castle and the Church of St James are first mentioned in the period 1135-54. It is clear therefore, that the borough with its recorded church had been founded at the latest by the middle of the 12th century and had been provided with earth and timber defences. In the middle of the 14th century, Kenfig was a substantial borough of perhaps 700-800 persons. 'High', 'East' and 'West' Streets are recorded, as well as a chapel to St Thomas, the Guildhall and a maladaria (hospital or leper house). Clearly the borough was flourishing at this time, though during the 15th century the situation deteriorated rapidly through sand encroachment.

By 1470, the town had been virtually abandoned. The following year the burgesses were instructed to leave their church and move to Pyle, where a new settlement was developing. By the 1530s the antiquary Leland noted only 'a village on the east side of Kenfik, and a Castel, both in ruins and almost shokid and devoured with the sandes that the Severne se there castith up'. By 1572, only three burgesses remained, while a borough survey of 1665 recorded only a single family living 'on the site of the ould castle'.

Apart from the castle at Kenfig (see above), the theme of medieval defence/military in the area is represented by the impressive site of Ogmore Castle (SAM Gm 37), a masonry castle of the 12th to 14th centuries strategically located next to a tidal ford across the Ewenny River, and also at the upper limits of the rivers normal tidal reach. It was originally built in earth and timber with a ditch designed to fill with water at high tide, and the early 12th century masonry keep subsequently erected within the inner ward is thought to be one of the oldest Norman stone buildings in South East Wales.

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Transport and industry

The castle at Kenfig (HLCA 004) lies not far from the point where the Roman road from Cardiff to Neath crossed the River Kenfig. This ancient road, the medieval Maritima or Port Way, was of Roman origin and the siting of the castle on this strategic thoroughfare, where the river meets the sea, was particularly well chosen. Today the castle and borough may best be located in relation to modern features, which in fact, in their own right today, bear testimony to the important position of Kenfig on communication lines. The castle borough lies immediately south of the mainline railway, and some 300m west of the point at which an elevated section of the M4 motorway crosses the railway.

The lordship, castle and early medieval borough of Kenfig derived their name from the once important river, the River Cynffig, which rises on Margam Mountain 6km to the north. The castle is situated on its south bank, 2km from the present estuary, though this is of late medieval origin. Originally a broad estuary existed which extended inland almost to the site of the castle, and this early and important geographical feature is evident today by the large land-locked Kenfig Pool and lesser ponds to the north. This original topography made the castle of Kenfig and its attendant borough strategically and militarily significant as they were placed on a port and river of some consequence (HLCA 004).

Similarly the location of Ogmore and Merthyr Mawr (HLCAs 013 and 016) near the upper limits of a tidal river have an obvious strategic and economic value, eg for tidal milling as at Ogmore. As well as being convenient boundaries, demarcating territory, navigable rivers and tidal estuaries would have had the important function of communication routes, providing harbourage, and collection of duties from shipping (cartographic evidence dating to c 1600 indicates shipping duties were collected on the north bank of the Ogmore River, downstream of Ogmore Castle). Like Kenfig, the area around Merthyr Mawr is characterised also by its proximity to major communication routes during the Roman and medieval periods, eg Heol-y-milwyr. River crossing/fording points and good examples of early bridges are important characteristics of the Merthyr Mawr/Ogmore area, emphasizing the importance of good transport networks to the area over the centuries.

The modern railway and road connections of the 19th and 20th centuries continue these characteristics, although bypassing or cutting through the historic landscape area rather than linking to points within (see HLCAs 001 and 011).

Industry in the area is small scale and closely linked to agriculture and settlement, ranging from prehistoric to the post-medieval period in date (eg Iron Age bloomery and post-medieval corn mill within the besanded landscape of Merthyr Mawr Warren HLCA 013).

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Agricultural landscapes

The post-medieval settlement and agricultural landscape at Kenfig (HLCA 007) is characterised by generally sparse linear ribbon style settlement development along the routes towards Maudlam church and the abandoned borough beyond. The settlement appears to have been imposed on an earlier surviving fieldscape of medieval linear strip fields or quillets, typified by dispersed individual holdings. The farmsteads are notably located at the margins of the holdings (more typical of the settlements of later landless agricultural labourers) and generally set within small groups within individual small linear plots, which are on a similar alignment to and respect the boundaries of the surviving medieval strip field system. This configures well with a late medieval/early post-medieval date for the displacement of the settlement of Kenfig, with the resultant settlement pattern reflecting the 'pre-enclosure' nature of the agricultural holdings then still prevalent.

To the south, the settlement at Merthyr Mawr (HLCA 012) is more characteristic of the villages of the Vale of Glamorgan to the east: a nucleated settlement, with manor, medieval church and mill and with a wealth of surviving regional houses of significant architectural and social interest. Ogmore is similar but on a smaller scale, a shrunken settlement, devastated by the effects of the Glyndwr Rebellion. The surrounding agricultural landscape retaining evidence of earlier medieval infield-outfield arrangement, with fossilised strip fields, and extensive water meadows at the confluence of the Ogmore and Ewenny Rivers.

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Funerary and ritual, and ecclesiastical landscapes

Evidence for prehistoric burial and associated ritual practice is provided by Bronze Age cairns from the area of Merthyr Mawr Warren (HLCA 013), Ogmore Down (HLCA 016) and the area around Sker (HLCA 009) in particular.

The most significant ecclesiastical landscape (HLCA 012) is centred on the medieval church at Merthyr Mawr, with its early dedication to St Teilo, has a collection of Early Christian stones (eg SAMs Gm 226 and Gm 169), including the Conbellin stone at Merthyr Mawr, suggesting the site might originally have been a monastic clas foundation (a unit of administration based on medieval monastic settlement). Another ecclesiastical site with potential early medieval origins is that of St Roques Chapel (SAM Gm 247) within the grounds of Merthyr Mawr House.

The location of the major early medieval churches of the area is indicated by a number of Early Christian inscribed stones; Merthyr Mawr was located within the historic landscape itself while Margam lay to the northeast. Both would have had influences over the spiritual and physical aspects of the landscape; the involved way in which this helped to shape the present landscape is beyond the remit of the current project and limitations of the broad brush methodology, and will, again, require more in-depth investigation.

Later during the medieval period the area was largely the property of the great Cistercian Abbey of Margam and later, in part, Neath Abbey, following the transferal of the grange at Sker (HLCA 009) to the latter. These granges were not overtly ecclesiastical in nature; being in effect ecclesiastical farms, usually operated by lay brothers, and by the end of the 14th century it was not uncommon for granges to be leased out to lay people.

The various granges associated with the Cistercian Abbeys of Margam and Neath had an important influence on the development of the landscape of the area in terms of agriculture and settlement; stock husbandry (ie cattle and in particular sheep) was further developed during monastic control of the area and indeed Margam became renowned as a wool producing centre; the Taxation of 1291 and poll tax return of 1379 indicate the large scale nature of sheep-farming during the period within the area's held by Margam (Owen 1989, 215; Cowley 1977, 86-9; Williams 1962, 174).

The resultant settlement pattern appears to have been one of dispersed farmsteads or granges around the perimeter of Mynydd Margam and along the coastal fringe. Llanmihangel Grange (RCAHMW, 1982, 280-2), fell on the boundary between the alluvial coastal plain and the solid geology with its great barn, and mill sites on the Kenfig, a water driven cornmill (Listed Grade II*) and a pandy or fulling mill (Llanmihangel millrace SAM Gm 449), was a possession of Margam Abbey. The other Margam granges within or with land holdings inside the historic landscape included New Grange alias Middle Burrows Grange (RCAHMW, 1982, 272-4), Morfa Mawr, and Theodorics Grange, a former hermitage granted to Margam in 1188, levelled for the steelworks in 1949 (Gray 1903, 121-31; Cowley 1963, 188-90; RCAHMW 1982, 271-2); Williams, 1990, 48-52). The latter were all constructed on reclaimed alluvial saltmarsh.

The grange at Sker was sold by Margam to Neath c 1175; here a blocked gateway and barn may be partly medieval (Evans 1956, 5-10; RCAHMW 1982, 254-5).

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The historic landscape is situated within the post-medieval County of Glamorgan, which prior to the Norman invasion was part of the early Kingdom of Glywysing, named after an eponymous early King, Glywys; during the 10th century the area became known as Morgannwg, from its ruler Morgan (Morcan) Hen (c 930-74), later Glamorgan, ('Gwlad Morgan') the medieval lordship (Knight 1995). According to tradition Glywysing or Morgannwg was divided into seven administrative regions or cantrefi, while 12th century sources assert that these were named after the sons of Glywys. Traditionally each cantref was divided into cwmwd, or commotes, each comprising estates or maenorau made up of a number of trefi, or townships. The exact form of the pre-Norman commotes of the area is largely speculative, however, a Cantref of Margam (Afan), which extended from the River Tawe with its southern boundary at either the River Cynffig (Kenfig) or Ogwr (Ogmore), the boundary of the medieval rural deanery of Kenfig, has been suggested (Knight 1995). This would place the historic landscape area of Merthyr Mawr, Kenfig and Margam Burrows largely within the area of the former cantref of Margam, possibly just straddling its southern border with Gorfynydd, if defined by the River Ogmore. The exact nature of the administrative, ecclesiastical and settlement landscape of the area during the early medieval period is at best speculative and would benefit from further in-depth research and study.

The antiquity of territorial boundaries in the area is hinted at by the surviving Vervil boundary dyke (SAM Gm 465), which delineates the southeast extent of the early medieval parish of Merthyr Mawr. Other ditched and banked boundaries have been noted nearby on aerial photographs, spanning the area between the Ogmore and Ewenny Rivers, some may even be prehistoric in origin.

Following the reorganisation of the area after the Norman annexation, the area of the present historic landscape was divided between Cynffig and the lordship of Tir Iarl, the latter being demesne land of the Earls of Gloucester, lords of Glamorgan (RCAHMW Vol III, pt 1a, 1991).

The importance of Margam as an administrative centre continued after the dissolution of the monasteries in 1536-7 and the crown sales of the former monastic properties of Margam (1540, 1543, and 1546). During the post-medieval period the main landholder in the area was the Margam estate under the Mansels and Talbot families. Other major landowning families with interests in the area were the Stradling, Bowen and Nicholl families of the Merthyr Mawr estate, and to a lesser extent the Edwin and Wyndham (Later earls of Dunraven) families of Dunraven.

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Parkland and picturesque landscape

The only parkland or picturesque landscape within the area is that of Merthyr Mawr itself (HLCA 012), a registered park and garden (Site Evaluation Grade I; Ref number: PGW (Gm) 12 (BRI), laid out between 1806 and 1838 by Sir John Nicholl around the relocated Merthyr Mawr House (1806-09, Listed Grade II).

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