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The Mynydd Hiraethog Historic Landscape

Historic Landscape Characterisation

Mynydd Hiraethog

The Natural Landscape

Mynydd Hiraethog, also known as the Denbigh Moors, forms a large upland area between the two major lowland valleys of North Wales, Dyffryn Conwy on the west and Dyffryn Clwyd (the Vale of Clwyd) on the east. It forms an undulating upland plateau, much of it above 400m above Ordnance Datum (OD) valley, dissected by stream valleys which drain northeastwards to the Conwy, northwards to the Elwy and Clwyd, and to the Alwen and Dee on the south and east.

The moor is subdivided into a number of distinct topographical blocks by these rivers and streams. The southern and northern areas of the moor are separated by the Afon Alwen, the natural headwater lake of Llyn Alwen, and by a number of stream valleys which feed the Afon Cledwen on the north-west side of the moor. The southern and western sides of the moor are dominated by a high ridge running from the peaks of Foelasfechan and Moel Seisiog on the west, through Moel Rhiwlug and Pen yr-orsedd to Mwdwl-eithin on the east, the latter at 532m above OD being the highest point of the moors.

The northern side of the moor which subdivides into a number of distinct blocks partly on topographical grounds and partly on the basis of modern land use. One large block lies between the valleys of the Afon Cledwen on the west and the Afon Aled and the headwater lake of Llyn Aled on the east, taking in Creigiau Llwydion, Llys Dymper, Bryn Euryn, Bryn Mawr and Moel y Gaseg-wen. A second block takes in the area north of the Alwen, east of the Aled and west of Llyn Brenig, taking in Moel Bengam, Bryn Trillyn, Gorsedd Bran and Bryn-y-gors-goch.

The eastern side of the moor includes the peaks of Tir Mostyn and Foel Goch, drops to a height of about 330m above OD below the dams of the Alwen and Brenig reservoirs and disappears below the cover of the Clocaenog Forest on the east. The two major valleys which dissect the moorland are now occupied by reservoirs. The Alwen valley which is relatively narrow and steep-sided contrasts with the Brenig valley which is broader and shallower, the two valleys joining at the confluence of the Afon Alwen and Afon Brenig a little beyond the boundary of the historic landscape area. A large natural lake had formed in the Brenig valley in the late glacial period which eventually escaped through a narrow gorge it cut through a large drumlin blocking the exit to the valley at the south, on about the site of the modern dam.

The geology of Mynydd Hiraethog is composed of a mixture of sedimentary rocks comprising Silurian grits, sandstones, mudstones and shales, much of the area being masked by glacial till and drumlins, particularly on the northern side of the moor (in the Creigiau Llwydion, Moel Bengam, Bryn-y-gors-goch, and Maen-llwyd character areas). Geology and hydrology have given rise to three basic soil types of varying quality, across the moor: loamy upland soils with peaty topsoil overlying rock (Hafren) supporting moorland and grassland habitats of moderate grazing value; seasonally waterlogged, gleyed and peaty soils overlying glacial till deposits (Wilcocks 2) supporting wet moorland pasture and some permanent grassland of moderate grazing value; and perennially wet raw peat soils overlying blanket and basin peat formations (Crowdy 2), supporting wet moorland and wetland habitats of poor to moderate grazing value. The present-day natural vegetation is dominated by grassland (Nardus strictus), peat formations and rushes in depressions, and by extensive areas of heather. Average rainfall is above 1250mm annually.

At face value at least, the place-names of Mynydd Hiraethog are wholly characteristic of the moorland character of the area, the names being dominated by topographical references including the elements moel/foel ('bare hilltop'), bryn/bryniau ('hill', 'hills'), clogwyn ('cliff'), craig/graig and creigiau ('crag', 'crags'), bron ('hill breast'), cefn ('ridge'), rhiw ('slope'), esgynfa ('rise'), and llech ('slate'). These are commonly described in terms of colour such as gwen/wen/wyn ('white'), du/ddu/duon ('black'), llwyd/llwydion ('grey', 'brown'), goch and rhudd ('red'), or in terms of size, such as mawr/fawr ('large'), fechan ('small'), and hir ('long'). Other colour descriptions include las ('green') and llaethog 'milky' with reference to pasture and a spring respectively. The shape of distinctively topographical features is sometimes described with reference to terms such as braich ('arm'), swch and trwyn ('tip') and mwdwl ('haycock', possibly with reference to the conical shape of the hill). Land use or the condition of land is indicated by a limited number of terms, including waen ('moorland') and ffridd/ffrith ('enclosed mountain pasture'), fawnog ('peat bog') typical moorland vegetation also being indicated by the terms eithin ('gorse'), onen/onnen ('ash') and criafolen ('rowan'). Water and water sources are referred to as rhaeadr ('waterfall'), ffynnon ('spring', 'well'), pwll ('pool'), llyn ('lake'), nant ('stream') and afon ('river'). Other specific landscape features of natural or artificial origin are denoted by terms such as maen ('stone'), other antiquities being called boncyn ('mound'), groes ('cross'), and carnedd/garnedd ('cairn'). Settlement is indicated by the terms and tai/ty ('house'), hafod/hafotty/fotty ('summer house'), and llys ('court'), as well as in the more specific name Hen Ddinbych ('Old Denbigh'), and meeting places are indicated by the term gorsedd/orsedd. Directions or relationships between settlements are indicated by the terms isaf ('lowest'), uchaf ('highest'), tan ('under') and pellaf ('furthest'). Apart from a number of proper names, people, often of an mythical character, are referred to be the elements Merddyn ('Merlin'), derwydd ('wizard'), heilyn ('cup-bearer') and clochydd ('sexton'). Ownership is indicated by the term tir ('land', 'territory') and possibly cynefir (?cynefin 'home') and terfyn ('boundary') and communications by naid-y-march ('horse leap') and bwlch ('pass'). Animals and birds are indicated by tarw ('bull'), march ('stallion'), gaseg ('mare'), ci ('dog'), dafad (sheep), bleiddiau ('wolves'), bran ('crow'), hydd ('deer'), hwyad ('duck'), and alarch ('swan'). Finally a sense of openness is emphasised by terms such as haul ('sun') and llannerch ('opening') and an evocative sense of bleakness ostensibly by the name hiraethog itself (perhaps to be translated as 'yearning'), though the origin of the name is open to question.

A few of the topographical names, such as Wauneos (gwenn eneas) and Moel Seisiog (Moel-seissiauc) can be traced back to the late 12th century, and Hiraethog itself, in the form Hir'hadok, to the late 13th century, but most name are of uncertain antiquity, many first appearing on the tithe maps of the 1840s or on published Ordnance Survey maps of the 1870s and 1880s. Some of the archaeological sites have names which are probably of some age. A number of Bronze Age burial mounds are named, including Boncyn Arian ('mound of the money'), possibly from the popular assumption that mounds of this kind concealed buried treasure. Other named prehistoric funerary monuments are Boncyn Crwn, Boncyn Cynefir Cleirrach, and Boncyn Melyn, together with the area names Pen-y-garnedd (carnedd, 'cairn') and Pen yr Orsedd (gorsedd) which might have similar connoations. Bryn yr Hen-groes ('hill of the old cross') may have its origin in a wayside cross on one of the many ancient trackways which meet near the head of the Afon Fechan, or possibly by reference to a three-legged sheep shelter built in the area. A number of place-names of antiquities or places appear to be quite recent however. Hen Ddinbych, the medieval enclosed settlement on the eastern side of the moor was first given this name in the 1860s. Sarn Helen is the name now given to stepping stones across the Aber Llech-Damer stream near Hen Ddinbych but which earlier, in the form Llwybr Elen or Sarn Elen, given to an important trackway along the Brenig valley further to the west.

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