Monday, 22 January 2018

Mapping Mountains – Hill Reclassifications – Y Pedwarau


Garth Fawr (SO 085 059) – Pedwar addition

There has been an addition to the listing of Y Pedwarau due to detail on OS Maps, which is the recent replacement for OS Get-a-map.  The Y Pedwarau is the title for the list of 400m hills of Wales and takes in all Welsh hills at and above 400m and below 500m in height that have a minimum 30m of drop, the list is a joint compilation between Myrddyn Phillips and Aled Williams and it commenced publication on Mapping Mountains on the 30.01.17.

The name of the hill is Garth Fawr and prior to analysis of contours on the OS Maps website this hill was not listed as it is a relatively recent man-made construction and is the result of waste spoil from the Ffos-y-fran opencast mine that is now considered solid and stable, therefore it does not possess any separate ring contours for the area of its summit on either the Ordnance Survey 1:50,000 Landranger or the 1:25,000 Explorer map.

Garth Fawr is situated in the Y Cymoedd – dwyreiniol range of hills and is placed in the Region of South Wales (Region C, Sub-Region C2).  The hill is positioned between the towns of Merthyr Tudful (Merthyr Tydfil) to its north-west and Rhymni (Rhymney) to its north-east and has the A 465 Heads of the Valleys Road to its north and the A 4060 road to its west.

As the summit of this hill is not a part of designated open access land permission to visit should be sought, for those wishing to do so a minor road to the south would give access to the hill.

Garth Fawr had little natural prominence and is a southerly spur of Twyn y Waun, but due to mining activity its height has increased with the 5m contour intervals on OS Maps giving it three separate uppermost 410m ring contours and a bwlch height of c 376m based on contouring between 375m – 380m, whilst LIDAR analysis conducted by Aled Williams gives the summit height as 388.0m at SO 08521 05968 and the height of the bwlch as 374.8m at SO 08618 06004.  It is apparent that the mine spoil was deposited after the measurement of LIDAR data was taken.  Therefore, as the hill is considered solid and stable these values are sufficient for it to be listed as a Pedwar with c 39m of drop.


The full details for the hill are:

Cardinal Hill:  Twyn y Waun
 
Summit Height:  c 414m

Name:  Garth Fawr

OS 1:50,000 map:  160

Summit Grid Reference:  SO 085 059

Drop:  c 39m


For the additions, deletions and reclassifications to the Y Pedwarau reported on Mapping Mountains since the May 2013 publication of the list by Europeaklist please consult the following Change Registers:









Garth Fawr (SO 085 059) is now classified as a Pedwar.  Photo: Rob Woodall

Myrddyn Phillips and Aled Williams (January 2018)







Sunday, 21 January 2018

Mapping Mountains – Significant Height Revisions – Y Pedwarau


Twyn y Waun (SO 085 065) 

There has been a Significant Height Revision to a summit of a hill that is now listed in the Y Pedwarau, and which was initiated by a survey with the Trimble GeoXH 6000, with the survey that confirmed this height revision being conducted on the 1st December 2017.

The criteria for the list this height revision affects are:

Y Pedwarau – All Welsh hills at and above 400m and below 500m in height that have 30m minimum drop.  Whilst the criteria for 400m Sub-Pedwar status are all Welsh hills at and above 400m and below 500m in height that have 20m or more and below 30m of drop.

The name of the hill is Twyn y Waun and this hill is the result of mine spoil from the Ffos-y-fran opencast mine, as a result it is considered a man-made hill.  It is situated in the Y Cymoedd – dwyreiniol range of hills which are in the central part of South Wales (Region C, Sub-Region C2), and it is positioned between the town of Merthyr Tudful (Merthyr Tydfil) to its west and Rhymni (Rhymney) to its east.

As this man-made hill is a part of a working mine permission to visit should be sought, for those wishing to do so a public footpath leaves the convenience of a near minor road to the north north-east of the hill.

Prior to the survey with the Trimble GeoXH 6000 this man-made hill was not classified although it had been noted; most recently by Rob Woodall who reported its approximate height and prominence.  This hill possesses no ring contour on Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps with the continuation of contours from the unmined land to the east of the hill being between 400m – 410m high compared to where the summit of this man-made hill is now situated. 

The resulting survey with the Trimble GeoXH 6000 produced a summit height of 460.5m (converted to OSGM15) and a bwlch height of 419.5m (converted to OSGM15), with these values giving this hill 41.0m of drop, with the summit height being a dramatic increase in height compared to the continuation of map contours from the unmined land to the east and therefore it comes within the parameters of the Significant Height Revisions used within this page heading, these parameters are:

The term Significant Height Revisions applies to any listed hill whose Ordnance Survey or Harvey map summit spot height has a 2m or more discrepancy when compared to the survey result produced by the Trimble GeoXH 6000, also included are hills whose summit map data is missing an uppermost ring contour when compared to the data produced by the Trimble.  As heights on different scaled Ordnance Survey maps are not consistent the height given on the 1:25,000 Explorer map is being prioritised in favour of the 1:50,000 Landranger map for detailing these revisions.

Therefore, the new height for this man-made hill 460.5m (converted to OSGM15), and as no contours exist for this hill on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps this is a dramatic 50.5m increase in height compared to the continuation of the 410m contour from the unmined land to the east of this hill.


The full details for the hill are:

Cardinal Hill:  Twyn y Waun

Summit Height (New Height):  460.5m (converted to OSGM15)

Name:  Twyn y Waun

OS 1:50,000 map:  160

Summit Grid Reference:  SO 08549 06591

Drop:  41.0m (converted to OSGM15)


The Trimble GeoXH 6000 gathering data at the summit of Twyn y Waun (SO 085 065) which resulted in this hill's significant height revision


Myrddyn Phillips and Aled Williams (January 2018)






Friday, 19 January 2018

Mapping Mountains – Hill Reclassifications – Y Pedwarau


Twyn y Waun (SO 085 065) – Pedwar addition

There has been an addition to the listing of Y Pedwarau due to a survey with the Trimble GeoXH 6000 that was instigated by an on-site visit by Rob Woodall and an article written by Aled Williams in 2015 entitled ‘Artificial Pedwar Hills.’  The Y Pedwarau is the title for the list of 400m hills of Wales and takes in all Welsh hills at and above 400m and below 500m in height that have a minimum 30m of drop, the list is a joint compilation between Myrddyn Phillips and Aled Williams and it commenced publication on Mapping Mountains on the 30.01.17.

The name of the hill is Twyn y Waun and prior to the Trimble GeoXH 6000 survey this hill was not listed as it is a relatively recent man-made construction and is the result of waste spoil that is now considered solid and stable from the Ffos-y-fran opencast mine, therefore it does not possess separate ring contours on either the Ordnance Survey 1:50,000 Landranger or the 1:25,000 Explorer map.

Twyn y Waun is situated in the Y Cymoedd – dwyreiniol range of hills and is placed in the Region of South Wales (Region C, Sub-Region C2).  The hill is positioned between the towns of Merthyr Tudful (Merthyr Tydfil) to its west and Rhymni (Rhymney) to its east and has the A 465 Heads of the Valleys Road to its north-west.

As the summit of this hill is not a part of designated open access land permission to visit should be sought, for those wishing to do so a minor road to the north north-east of the hill gives access to a public footpath and a track that heads toward the critical bwlch of this hill.

The survey with the Trimble GeoXH 6000 resulted in a summit height of 460.5m (converted to OSGM15) and a bwlch height of 419.5m (converted to OSGM15), with these values giving this hill 41.0m of drop, and as this artificial hill is considered to be solid and stable in character these values are sufficient for it to be classified as a Pedwar.


The full details for the hill are:

Cardinal Hill:  Twyn y Waun 

Summit Height:  460.5m

Name:  Twyn y Waun

OS 1:50,000 map:  160

Summit Grid Reference:  SO 08549 06591

Drop:  41.0m


For the additions, deletions and reclassifications to the Y Pedwarau reported on Mapping Mountains since the May 2013 publication of the list by Europeaklist please consult the following Change Registers:










Twyn y Waun (SO 085 065) is now included as a Pedwar

For details on the survey of Twyn y Waun

Myrddyn Phillips and Aled Williams (January 2018)






Thursday, 18 January 2018

Mapping Mountains – Hill Reclassifications – Humps


Twyn y Waun (SO 082 070) – Recommended Subhump addition

This is the thirty first in a series of Hill Reclassification posts that detail hills whose status has either been altered in the listing of the Humps (HUndred Metre Prominences) through map study and / or surveys that I have instigated, or it is the recommendation that their status is altered.

The artificial summit of Twyn y Waun (SO 082 070)

Many preceding posts detailing these alterations to the Humps are retrospective as these hill reclassifications were either initiated from studying the Ordnance Survey Interactive Coverage Map that is hosted on the Geograph website, or initiated from a survey with the Trimble GeoXH 6000, and for the recommended addition that affects the Humps the survey of this hill took place on the 01.12.17.

The listing of Humps was published in book format by Lulu in 2009 and entitled More Relative Hills of Britain, its author; Mark Jackson gives credit to a number of people who contributed toward the formation of this list, these include; Eric Yeaman, Alan Dawson, Clem Clements, Rob Woodall, Bernie Hughes, Pete Ridges and others.  When the list was published in book format there were 2987 Humps listed with their criteria being any British hill that has 100m or more of drop, accompanying the main list is a sub category entitled Subhumps, with the criteria being any British hill that has 90m or more and below 100m of drop.

More Relative Hills of Britain by Mark Jackson

The details for the recommended reclassification appear below:

There has been a recommended reclassification to the listing of the Humps (HUndred Metre Prominences) instigated by a survey with the Trimble GeoXH 6000 which took place on the 01.12.17.

This hill has an intact natural summit and an artificial summit that now overshadows it and Mark Jackson lists this hill with 63m of drop based on an estimated c 451m height for the natural summit which has an uppermost 450m contour on the Ordnance Survey 1:50,000 Landranger map and the Interactive Coverage Map hosted on the Geograph website, and an estimated bwlch height of 388m based on bwlch contouring at 10m intervals and between 380m – 390m on the 1:25,000 Explorer map.  However, OS Maps which is the recent replacement for OS Get-a-map gives bwlch contouring at 5m intervals and between 375m – 380m, with the latter height taking in the width of a road and indicating an estimated bwlch height of c 380m, which if the artificial summit was taken for that of the hill gives this hill c 96m of drop. 

The natural summit of Twyn y Waun is now overshadowed by its artificial summit

Twyn y Waun is adjoined to the Y Cymoedd – dwyreiniol group of hills and is positioned between the town of Merthyr Tudful (Merthyr Tydfil) to its west and Rhymni (Rhymney) to its east and has the A 465 Heads of the Valleys Road to its north-west.

Therefore, if the artificial summit is taken as that for the hill it is recommended that its status is amended to that of Subhump.


The full details for the hill are:


Name:  Twn y Waun (as listed in the Tumps)

Summit Height:  451m (as listed in the Tumps) (476.0m [converted to OSGM15] artificial summit)

OS 1:50,000 map:  160

OS 1:25,000 map:  12, 166

Summit Grid Reference:  SO 08457 07348 (as listed in the Tumps) (artificial summit at SO 08209 07041)

Drop:  63m (as listed in the Tumps) (c 96m artificial summit)


Myrddyn Phillips (January 2018)



Wednesday, 17 January 2018

Dual Summits - Introduction


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.

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.

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.

Twyn y Waun is an example of a Dual Summit, with its c 451m natural summit (SO 08457 07348) in the foreground and its 476.0m man-made summit (SO 08209 07041) in the background on the right

As well as the status of a Dual Summit hill being reliant upon the artificial summit being created by man via in the main quarrying activity, man can also take away as artificial hills can also be levelled and the remaining land thereafter landscaped.  For those hills listed as Dual Summit hills that undergo a levelling process in the future their resulting status will be amended accordingly.

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.


Aled Williams and Myrddyn Phillips (January 2018)









Tuesday, 16 January 2018

Mapping Mountains – Hill Reclassifications – Y Pedwarau


Twyn y Waun (artificial summit at SO 082 070 and natural summit at SO 084 073) – Pedwar reclassified to Dual Summit Pedwar

There has been a reclassification to the listing of Y Pedwarau due to a survey with the Trimble GeoXH 6000 that was instigated by an on-site visit by Rob Woodall and an article written by Aled Williams in 2015 and entitled ‘Artificial Pedwar Hills.’  The Y Pedwarau is the title for the list of 400m hills of Wales and takes in all Welsh hills at and above 400m and below 500m in height that have a minimum 30m of drop, the list is a joint compilation between Myrddyn Phillips and Aled Williams and it commenced publication on Mapping Mountains on the 30.01.17.

Accompanying the main Y Pedwarau list are five categories of sub hills, however this hill has not been reclassified from one of these categories to another, as a new classification of Dual Summit has been created to accommodate the details relating to this hill.

Dual Summit hills:

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, with the latter that can be described as stable in character.  In the main, these recent man-made constructions are the result of quarrying activities producing spoil tips.  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.  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.

The name of the hill is Twyn y Waun and prior to the Trimble GeoXH 6000 survey this hill was listed with an estimated c 451m summit height based on a 450m uppermost contour on the Ordnance Survey 1:50,000 map and the Interactive Coverage Map hosted on the Geograph website and a drop of c 63m which has now been re-evaluated.

Twyn y Waun is situated in the Y Cymoedd – dwyreiniol range of hills and is listed as a Cardinal Hill, and is placed in the Region of South Wales (Region C, Sub-Region C2).  The hill is positioned between the towns of Merthyr Tudful (Merthyr Tydfil) to its west and Rhymni (Rhymney) to its east and has the A 465 Heads of the Valleys Road to its north-west.

Twyn y Waun is now listed as a Dual Summit hill and its natural summit is a part of designated open access land and can be approached from the convenience of a minor road to its east, whilst as its man-made summit is a part of a working mine permission to visit should be sought, however the artificial summit is on the border of designated open access land shown on the Ordnance Survey 1:25,000 Explorer map, and for those wishing to visit an ascent of this artificial summit from the natural summit is  an easy extension of the short walk from the minor road to the east.


The full details for the hill are:

Cardinal Hill:  Twyn y Waun 

Summit Height:  476.0m (artificial Dual Summit) c 451m (natural Dual Summit)

Name:  Twyn y Waun

OS 1:50,000 map:  160

Summit Grid Reference:  SO 08209 07041 (artificial Dual Summit) SO 08457 07348 (natural Dual Summit)

Drop:  c 96m (artificial Dual Summit) c 71m (natural Dual Summit)


For the additions, deletions and reclassifications to the Y Pedwarau reported on Mapping Mountains since the May 2013 publication of the list by Europeaklist please consult the following Change Registers:

The Dual Summit of Twyn y Waun with the pastoral natural summit in the foreground and the man-made summit in the background










Myrddyn Phillips and Aled Williams (January 2018)