Y Pedwarau – Two new Pedwar hills and re-classification of an existing Pedwar to Dual Summit status

The Pedwar listing has been updated with the addition of two new Pedwar hills and the re-classification of an existing Pedwar to Dual Summit status, all of these hills are in close proximity of one another and situated to the east of Merthyr Tudful in south Wales.

Dual Summit:  Twyn y Waun    476.0m (artificial) at SO 08209 07041 / 450.6m (natural) at SO 08442 07378

Firstly, a note on the term ‘Dual Summit’.

A hill classified as a Dual Summit is defined as one which has an extant natural summit coupled with that of a higher artificial summit, which can be described as being stable in character.  In the main, these recent man-made constructions are the result of quarrying activities producing spoil tips and to put a spin on the term ‘Dual Summit’, the natural and artificial summits of such hills could be thought of as duelling with each other for the merit of summit status, which well describes the polarising affect that such instances can have on the hill bagger, with some baggers preferring to ignore the artificial summit in favour of the natural high point and vice versa.  For those bagging Dual Summit hills, a visit to either the natural high point or the elevated man-made high point is sufficient to claim an ascent of the hill.

These recent man-made constructions are treated differently to ancient man-made constructions such as hill forts and tumuli, as if the latter are deemed stable and of an earthen character their age dictates that they can be viewed as being permanent in nature and are now effectively a part of the hill.  The concept of a ‘dual summit’ is a new one, having been devised by the authors of the Y Pedwarau listing in response to the circumstances of the following Pedwar hill.

Twyn y Waun is now considered a Dual Summit hill with its remaining natural high point positioned at SO 08442 07378 and listed with a height of 450.6m derived from a Trimble GeoXH 6000 survey, whilst the man-made construction which dominates this hill has its summit positioned at SO 08209 07041 and has a height of 476.0m.  The remains of the natural summit of this hill still exists and consists of undistinguished grazing pasture, it is now overshadowed by a man-made construction consisting of waste spoil from the Ffos-y-fran opencast mine.  The man-made construction is considered stable and can be easily climbed and consists of grassed side slopes and in the main solid waste spoil on the summit area which is interspersed with patches of grass. 

The 450.6m natural summit of Twyn y Waun is now overshadowed by its 476.0m artificial Dual Summit

The elevated man-made construction is situated on the edge of the natural summit area of Twyn y Waun and is known by mine employees as the North Tip and Overburden 1 (OB1), as it is an overburden mound from the mine extraction.  This Dual Summit hill has a prominence of 96.0m (artificial) / 70.7m (natural) and therefore if the elevated man-made construction is taken, it is a prospective new Subhump.

The 476.0m artificial Dual Summit of Twyn y Waun

As detailed above, the artificial summit of Twyn y Waun was surveyed by Myrddyn Phillips using the Trimble GeoXH 6000, with the survey having been instigated by a recent Facebook and Tump Forum post by Rob Woodall. 

New Pedwar:  Twyn y Waun    460.5m artificial summit at SO 08549 06591

This hill is a new artificial Pedwar and consists of waste spoil from the Ffos-y-fran opencast mine.  The man-made hill is considered stable and can be easily climbed and consists of grassed side slopes and in the main a grassed summit area.  This hill was created on the southern slope of Twyn y Waun and is known by mine employees as the South Tip and Overburden 2 (OB2), as it is an overburden mound from the mine extraction.  It has an artificial prominence of 41.0m.

The 460.5m artificial summit of one of the two new Pedwar hills

The survey of this hill had been on our surveying radar for some time, having been detailed in a 2015 document entitled ‘Artificial Pedwar Hills’ by Aled Williams, and was finally prompted by a recent visit communicated to Myrddyn Phillips by Rob Woodall. 

New Pedwar:  Garth Fawr    410m artificial summit at SO 082 059

This artificial hill is positioned to the south of the Ffos-y-fran mine and to the knowledge of the authors, it currently has no recorded summit visit from anyone in the hill bagging community, therefore its inclusion as a Pedwar is reliant upon detail from OS Maps (the recent replacement for OS Get-a-map) and independent visual inspection, albeit from a distance, by Rob Woodall and Myrddyn Phillips. 

The 410m artificial summit of Garth Fawr; the second of the two new Pedwar hills.  Photo:  Rob Woodall

Garth Fawr had been on our surveying radar for some time, having been detailed in a 2015 document entitled ‘Artificial Pedwar Hills’ by Aled Williams.  In early 2017, Aled Williams analysed LIDAR data for this area and recorded a summit height of 388.0m at SO 08521 05968 and a bwlch height of 374.8m at SO 08618 06004, giving a drop of 13.2m.  In late 2017, Myrddyn Phillips was contacted by Rob Woodall who reported that an unrecorded artificial hill existed on the spur known as Garth Fawr.

Garth Fawr had little natural prominence and was a southerly spur of Twyn y Waun, but due to mining activity its height has increased with OS Maps giving it three separate uppermost ring contours of 410m and a bwlch height of c 376m based on contouring between 375m – 380m, whilst LIDAR analysis conducted by Aled Williams gives the height of the bwlch as 374.8m at SO 08618 06004.  It is apparent that the mine spoil was deposited post measurement of the LIDAR data.  The northern slopes of the hill are grassed and the summit area consists of waste spoil, which is undoubtedly of a stable character.  This man-made hill is known by mine employees as Overburden 3 (OB3), as it is an overburden mound from the mine extraction.  It has an artificial prominence of c 35m.

As the mining activity in the area is ongoing, these summits could undergo a levelling process in the future.  If this does occur, the Y Pedwarau - The 400m Hills of Wales listing will be updated accordingly.

Myrddyn Phillips and Aled Williams (December 2017)