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Mynydd Hiraethog Historic Landscape
Character area map

Historic Landscape Characterisation

Mynydd Hiraethog: Creigiau Llwydion
Llangernyw, Llansannan and Pentrefoelas, Conwy
(HLCA 1102)

CPAT PHOTO cs013128

Unenclosed moorland on northern edge of Mynydd Hiraethog with discrete medieval and later encroachments.

Historic background

Though there is relatively little surviving evidence above ground, early land use history for the area is provided by the study of peat deposits on Cefn Mawr, west of Llyn Aled. The earliest evidence of human activity belongs to the period about 3000 BC, though relatively little impact on the natural environment is evident until the period between 1900-1000 BC which saw a marked decline in woodland species and a rise in grasses and herbs. Peat deposits of the period between 1000-200 BC appear to show some evidence of agricultural activity together with burning possibly to control advancing heather moorland. The period between 200 BC up to the present shows a steady increase in heather moorland and an increase in peat formation possibly due to climatic change.

The area falls within the 19th-century tithe parishes of Gwytherin, Llanfair Talhaiarn, Llansannan and Tiryrabad-isaf (Pentrefoelas). Little archaeological fieldwork has been undertaken in much of the area in recent years apart from some intensive survey along the eastern margins, carried out in the 1990s.

Key historic landscape characteristics

The character area occupies almost 18km2 of moorland on the northern edge of Mynydd Hiraethog, overlooking the Cledwen valley. It lies to the north of Llyn Alwen and west of Llyn Aled and Aled Isaf Reservoir, and lies between a height of about 290-465m above Ordnance Datum, and includes the summits of Bryn Euryn, Pen Bryn y Clochydd and Cefn Mawr as well as that of Creigiau Llwydion. The area looks predominantly to the north and east. Drainage is to the Afon Elwy river system to north by the Wauneos, Nant Caledfryn and Nant Goch, tributaries of the Afon Cledwen, to the north-east by the Nant Bach and Afon Aled, and to the Dee river system to the south by means of the Afon Alwen.

Settlement is represented by a number of discrete encroachments onto the common formerly with two or three farmsteads, typically around the head of a stream or close to the natural upland lakes of Llyn Alwen and Llyn Aled, and set within groups of fields between often about 35-60ha in extent, at a height of 370m above Ordnance Datum. A number of the farmsteads are associated with hafod names, as at Hafod-gau and Pant-y-fotty, which may have originated as medieval or early post-medieval seasonally occupied houses which subsequently turned into permanently occupied farmsteads. Other possibly seasonally-occupied dwellings of medieval or post-medieval date which may not have undergone the transformation to permanently occupied farmsteads appear to be represented by isolated platforms or long-hut foundations on the south-facing slopes towards the head of the Afon Alwen, unassociated with field enclosures, but there are also a number of the later farmsteads, such as Rhwngyddwyffordd, which were only built after about the middle of the 19th century. Many of the farmsteads appear to have been abandoned in the later 19th or earlier 20th century. Some are now in ruins though others are used for storage or converted into sheepfolds. In their original form many of the 18th- and earlier 19th-century dwellings were low, single-storey, stone-built structures with central chimney, and often only accompanied by a small outhouse and occasionally by a pigsty, some of the houses being associated with small stone quarries which evidently provided the source of building materials.

Agricultural activity represented by a number of clearance cairns in the area between Llyn Alwen, Llyn Aled and Aled Isaf Reservoir. Some are associated with the medieval and later encroachments onto the common though others, as on the western edge of Aled Isaf, are isolated and possibly of earlier date. Cultivation ridges as at Waen-isaf-las are also visible within a number of enclosed fields. The field boundaries associated with the encroachments are generally of medium-sized earth and stone banks, sometimes surmounted by modern post-and-wire fences. Some of the enclosed fields have been retained as areas of improved pasture despite the abandonment of associated dwellings, though in other cases former fields have reverted to a rough heather moorland vegetation. Characteristic of the moorland edge, the stream valleys and more isolated moorland areas are sheepfolds, sheep shelters and sheep-dips of drystone or post-and-tin construction, some abandoned and some still in use, a number of which are shown on early editions of the Ordnance Survey and were already in existence by the later 19th century.

Prehistoric burial is represented by several scattered stone monuments, including the large and impressive burial cairn known as Boncyn Crwn, on a ridge near the moorland edge and visible from lower ground as well as the cairn with burial cist on Moel-y-gaseg, within the heart of the moorland area, both possibly marking territories of Bronze Age communities which exploited the moor. Possible prehistoric standing stones are also known in the area. Some of the much later boundaries between the Llanfair Talhaiarn and Gwytherin, Llanfair Talhaiarn and Llansannan, and Llansannan and Tiryrabad-isaf (Pentrefoelas) tithe parishes are marked by remarkable stone settings, some at 50-100m intervals. In some cases these correspond to marking stones shown on the mid 19th-century tithe maps and in some instances probably dating back to the later 18th century or earlier.

Transport and communication is largely confined to footpaths and trackways, some probably of considerable antiquity, linking upland pastures and once linked isolated farmsteads with lower-lying farms in the parishes of Gwytherin, Llanfair Talhaiarn and Llansannan. Former peat-cutting carried out on a domestic scale is represented by peat mounds and drying platforms in a number of the stream valleys west of Llyn Aled and Aled Isaf reservoirs and in the valley of the Nant Goch, at the head of the Afon Cledwen.


CPAT Sites and Monuments Record;
Davies 1977;
Gwytherin, Llanfair Talhaiarn, and Llansannan tithe maps and apportionments;
Owen & Silvester 1993

For further information please contact the Clwyd-Powys Archaeological Trust at this address, or link to the Countryside Council for Wales' web site at

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