Friday, 31 March 2017

Mapping Mountains – Significant Name Changes – 200m Twmpau and Y Trechol - The Dominant Hills of Wales


Cefn Nedd (SO 185 965)

There has been a Significant Name Change to a hill that is listed in the 200m Twmpau and Y Trechol - The Dominant Hills of Waleswith the height, drop, dominance and status of the hill being confirmed by a Trimble GeoXH 6000 survey which took place on the 9th March 2017.

The criteria for the two lists that this name change applies to are:

200m Twmpau - All Welsh hills at and above 200m and below 300m in height that have 30m minimum drop, with the word Twmpau being an acronym standing for thirty welsh metre prominences and upward.

Y Trechol - The Dominant Hills of Wales - These are the Welsh P30 hills whose prominence equal or exceed half that of their absolute height.  With the criteria for Lesser Dominant status being those addition Welsh P30 hills whose prominence is 33% or more and below 50% of their absolute height.  

The hill is adjoined to the Beacon Hill range, this group of hills is situated in the north-eastern part of Mid and West Wales (Region B, Sub-Region B1), and the hill is positioned above the B 4385 and the A 483 roads with the Afon Hafren (River Severn) between each, and has the small town of Trefaldwyn (Montgomery) to the east and the village of Aber-miwl (Abermule) to the south-west. 

The Trimble GeoXH 6000 gathering data at the summit of Cefn Nedd

The hill appeared in the 200m P30 list on Geoff Crowder’s v-g.me website under the name Goron-ddu.  During my early hill listing I paid little regard to name placement on a map, or the meaning of names and to what feature the name was appropriately applied to.  Therefore I prioritised names for listing purposes that I now understand are either inappropriate or where another name is viewed as being more appropriate, and Goron Ddu is such an example as this name has been consistently applied by the Ordnance Survey to land taking in the lower north-westerly slopes of this hill, and not necessarily to the hill itself or its summit, and importantly the placement of this name in relation to the land it is applicable to has also been substantiated by local enquiry, including with the landowner.  The former is not a practice that I now advocate as with time and inclination place-name data can be improved either by asking local people or by examining historical documents, through this form of research an appropriate name for the hill can usually be found, and in the case of this hill the name of Cefn Nedd was derived from the Tithe map.  


Goron-ddu      207m      SO185965      136  216
  

Extract from the Ordnance Survey 1:25,000 Historical map showing the placement of the name Gorun-ddu

Alan Harding was the second local farmer who substantiated the land that the name of Gorun Ddu is applicable to, and this matches the name placement on the above map, he also put me in contact with the land owner who also substantiated the placement of Gorun Ddu to be on the lower north-westerly slopes of this hill

The current Ordnance Survey 1:25,000 Explorer map is not the best for name placement

The term Tithe map is generally given to a map of a Welsh or English parish or township and which was prepared after the 1836 Tithe Commutation Act.  This act allowed tithes to be paid in cash rather than goods.  The Tithe maps gave names of owners and occupiers of land in each parish and importantly for place-name research they also included the name of enclosed land.  This enclosed land is usually based on a field system, however not every field is given a name, but many are and especially so in Wales.

The enclosed land taking in the summit is given the number 551 on the Tithe map

The enclosed land where the summit of this hill is situated is given the number 551 on the Tithe map, this can be cross referenced against the apportionments; it is these apportionments that give the name of the owner or occupier of the land as well as the name of the land.  The land where the summit of this hill is situated is named as Cefn Nedd on the Tithe map and described as Cloverley; it appears in the county named as Montgomery and in the parish of Llandysul.

When cross referenced in the apportionments the enclosed land is named as Cefn Nedd

Therefore, the name this hill is now listed by in the 200m Twmpau and Y Trechol - The Dominant Hills of Wales is Cefn Nedd, and this was derived from the Tithe map. 


The full details for the hill are:

Group:  Beacon Hill

Name:  Cefn Nedd

Previously Listed Name:  Goron-ddu 

Summit Height:  207.2m (converted to OSGM15)

OS 1:50,000 map:  136

Summit Grid Reference:  SO 18524 96503  

Drop:  89.1m (converted to OSGM15)

Dominance:  42.99%





Myrddyn Phillips (March 2017)











Wednesday, 29 March 2017

Mapping Mountains – Hill Reclassifications – 200m Twmpau


Mynydd y Drum (SN 807 097) - 200m Twmpau reclassified to 200m Sub-Twmpau

There has been a reclassification to the listing of Twmpau (thirty welsh metre prominences and upward) hills due to analysis of LIDAR data by Kevin McGovern and also independently by Aled Williams, and subsequently confirmed via a survey with the Trimble GeoXH 6000.  The hill has been reclassified from a 200m Twmpau to a 200m Sub-Twmpau, with the criteria for the former being all hills in Wales at or above 200m and below 300m in height that have a minimum drop of 30m, and the criteria for the sub category being all hills in Wales at or above 200m and below 300m in height with 20m or more and below 30m of drop.

The hill had been listed with an estimated drop of c 53m based on an estimated bwlch height of c 244m and the 297m summit height positioned at SN 807 098 derived from the spot height that appears on the Ordnance Survey 1:25,000 Explorer map numbers 12 and 165, whilst the Ordnance Survey 1:50,000 Landranger map number 160 gives a 298m summit spot height at the same position.  This latter spot height is derived from the 978.1ft (298.1ft) height on the Ordnance Survey old Six-Inch map.

When this hill was originally listed in the Welsh P30 lists on the v-g.me website it had an accompanying note which stated ‘3 points of 300m on 1985 map may probably no longer exist (quarrying)’.  The hand written Master List stated ‘Due to opencast workings the three points of 300c at GR 830 112 on 1985 1:50,000 map probably no longer exist’.  These three points are in the vicinity of where a 984ft (299.9m) height appears on the Ordnance Survey old Six Inch map and in all likelihood signified where the summit of this hill was once positioned.  Since this time the opencast workings which take in the northern and eastern part of the larger hill known as Mynydd y Drum have destroyed the old 984ft (299.9m) summit, but in its place are two separate hills comprising the spoil from the mine workings, with this Hill Reclassifications post concentrating on the remaining ‘natural’ and now lower of these three summits. 

Prior to analysis of LIDAR data Mynydd y Drum was listed with one summit, but due to opencast mining a further two summits have been created which are artificial and comprise the remains of waste spoil, the hill which this Hill Reclassifications post details is the remaining ‘natural’ summit, which is now lower in height compared to the two artificial summits, this has resulted in new bylchau heights and positions and also drop values for these three hills, all of these will be detailed in this and the two previous Hill Reclassifications posts, with the other two hills being Teisen Priodas (SN 820 108) and MRF Tip (SN 828 114).

The hill is adjoined to the Fforest Fawr group with its Cardinal Hill being Fan Gyhirych (SN 880 191) and is placed in the Region of South Wales (Region C, Sub-Region C2), and is positioned between the small town of Ystradgynlais to the north-west and the village of Blaendulais (Seven Sisters) to the south-east.

The upper part of the hill is situated within open access land and can be easily accessed from a number of public footpaths that emanate from Cwm Tawe (Swansea Valley) to the north-west and from Cwm Dulais (Dulais valley) from the south-east.

The name of the hill is Mynydd y Drum and its reclassification to a 200m Sub-Twmpau is due to the analysis of LIDAR data by Kevin McGovern and also independently by Aled Williams.  LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales.

Kevin’s analysis of LIDAR data gives the hill the following details:


Mynydd y Drum

Summit Height:  296.1m (converted to OSGM15)

Summit Grid Reference:  SN 80720 09754

Bwlch Height:  271.8m (converted to OSGM15)

Bwlch Grid Reference:  SN 81526 10520

Drop:  24.3m


Therefore, the 296.1m LIDAR data produced for the summit position at SN 80720 09754 and the 271.8m LIDAR data produced for the bwlch position at SN 81526 10520 is sufficient for this hill to be reclassified from a 200m Twmpau to a 200m Sub-Twmpau with 24.3m of drop, with the details from the Trimble GeoXH 6000 survey being 296.2m (converted to OSGM15) summit at SN 80718 09753 and 271.4m bwlch (converted to OSGM15) at SN 81526 10519), giving this hill 24.8m of drop.

This now revises the total in the 200m Twmpau and the list will be updated accordingly.


The full details for the hill are:

Cardinal Hill:  Fan Gyhirych

Summit Height:  296.2m (converted to OSGM15, Trimble data)

Name:  Mynydd y Drum

OS 1:50,000 map:  160

Summit Grid Reference:  SN 80718 09753 
  
Drop:  24.8m (converted to OSGM15, Trimble data)


Mynydd y Drum (SN 807 097) now reclassified to a 200m Sub-Twmpau

My thanks to Mark Jackson for bringing the details of this hill to my attention, and to Kevin McGovern and Aled Williams for their analysis of LIDAR data.



Myrddyn Phillips (March 2017)

Tuesday, 28 March 2017

Mapping Mountains – Hill Reclassifications – Y Trichant


MRF Tip (SN 828 114) - Trichant addition

There has been an addition to the listing of the Y Trichant, these are the hills within the 300m height band of the Twmpau (thirty welsh metre prominences and upward) due to analysis of LIDAR data by Kevin McGovern and also independently by Aled Williams.  The Y Trichant takes in all hills in Wales at or above 300m and below 400m in height that have a minimum drop of 30m.

Prior to analysis of LIDAR data the ridge known as Mynydd y Drum was listed with one summit, but due to opencast mining a further two summits have been created which are artificial and comprise the remains of waste spoil, the summit which this Hill Reclassifications post details is the lower of these two artificial hills, this has resulted in new bylchau heights and positions and also drop values for these three hills, all of these will be detailed in this and the previous and next Hill Reclassifications posts, with the name MRF Tip being found from local enquiry and the other two hills being Mynydd y Drum (SN 807 097) and Teisen Priodas (SN 820 108).

The hill is adjoined to the Fforest Fawr group with its Cardinal Hill being Fan Gyhirych (SN 880 191) and is placed in the Region of South Wales (Region C, Sub-Region C2), and it is positioned between the small communities of Abercraf (Abercrave) to the north-west and Y Coelbren towards the east.

The summit of the hill is situated within the Nant Helen Opencast Mine so permission to visit the high point should be sought, however it has open access land to its east and a little farther away to its south, and two public footpaths are marked on Ordnance Survey maps that head extremely close to the summit of this hill.

The name of the hill is MRF Tip and its reclassification to a Trichant is due to the analysis of LIDAR data by Kevin McGovern and also independently by Aled Williams.  LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales.

Kevin’s analysis of LIDAR data gives the hill the following details:


MRF Tip

Summit Height:  311.8m (converted to OSGM15)

Summit Grid Reference:  SN 82850 11432

Bwlch Height:  277.6m (converted to OSGM15)

Bwlch Grid Reference:  SN 82186 11128

Drop:  34.2m


Therefore, the 311.8m LIDAR data produced for the summit position at SN 82850 11432 and the 277.6m LIDAR data produced for the bwlch position at SN 82186 11128 is sufficient for this hill to be classified as a Trichant with 34.2m of drop.

This now revises the total in the Y Trichant and the Twmpau and the lists will be updated accordingly.


The full details for the hill are:

Cardinal Hill:  Fan Gyhirych

Summit Height:  311.8m (LIDAR data, converted to OSGM15)

Name:  MRF Tip

OS 1:50,000 map:  160

Summit Grid Reference:  SN 82850 11432
   
Drop:  34.2m (LIDAR data, converted to OSGM15)


MRF Tip (SN 828 114) now listed as a Trichant

My thanks to Mark Jackson for bringing the details of this hill to my attention and to Kevin McGovern and Aled Williams for their analysis of LIDAR data.


Myrddyn Phillips (March 2017)

Monday, 27 March 2017

Mapping Mountains – Hill Reclassifications – Y Trichant


Teisen Priodas (SN 820 108) - Trichant addition

There has been an addition to the listing of the Y Trichant, these are the hills within the 300m height band of the Twmpau (thirty welsh metre prominences and upward) due to analysis of LIDAR data by Kevin McGovern and also independently by Aled Williams, and subsequently confirmed via a survey with the Trimble GeoXH 6000.  With the high point of the hill previously listed in the 200m height band when the Welsh P30 hills below 500m in height were published on Geoff Crowder’s v-g.me website.

The hill had been listed with a 297m summit height positioned at SN 807 098 based on the spot height that appears on the Ordnance Survey 1:25,000 Explorer map numbers 12 and 165, whilst the Ordnance Survey 1:50,000 Landranger map number 160 gives a 298m summit spot height at the same position.  This latter spot height is derived from the 978.1ft (298.1ft) height on the Ordnance Survey old Six-Inch map.

When this hill was originally listed in the Welsh P30 lists on the v-g.me website it had an accompanying note which stated ‘3 points of 300m on 1985 map may probably no longer exist (quarrying)’.  The hand written Master Lists stated ‘Due to opencast workings the three points of 300c at GR 830 112 on 1985 1:50,000 map probably no longer exist’.  These three points are in the vicinity of where a 984ft (299.9m) height appears on the Ordnance Survey old Six Inch map and in all likelihood signified where the summit of this hill was once positioned.  Since this time the Nant Helen Openacast Mine workings which take in the northern and eastern part of the ridge known as Mynydd y Drum have destroyed the old 984ft (299.9m) summit, but in its place are two new P30 summits comprising the spoil from the mine workings, with this Hill Reclassifications post concentrating on the higher of these two artificial summits, whilst the 296.2m (converted to OSGM15) natural summit at SN 80718 09753 and listed as Mynydd y Drum still remains. 
  
Prior to analysis of LIDAR data the ridge known as Mynydd y Drum was listed with one summit, the opencast mine has now created a further two summits which are artificial and comprise the remains of waste spoil, the summit which this Hill Reclassifications post details is now higher than the previously listed summit, resulting in new bylchau heights and positions and also drop values for these three hills, all of these will be detailed in this and two further Hill Reclassifications posts, with the name Teisen Priodas being found from local enquiry and the other two hills being Mynydd y Drum (SN 807 097) and MRF Tip (SN 828 114).

The hill is adjoined to the Fforest Fawr group with its Cardinal Hill being Fan Gyhirych (SN 880 191) and is placed in the Region of South Wales (Region C, Sub-Region C2), and it is positioned between the small communities of Abercraf (Abercrave) to the north and Y Coelbren towards the east.

The summit of the hill is situated within the Nant Helen Opencast Mine so permission to visit the high point should be sought, however it has open access land to its south-west and a public footpath marked on Ordnance Survey maps that heads in a north- south direction and at its closest point is just to the west of the summit of this hill.

The name of the hill is Teisen Priodas and its reclassification to a Trichant is due to the analysis of LIDAR data by Kevin McGovern and also independently by Aled Williams.  LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales.

Kevin’s analysis of LIDAR data gives the hill the following details:


Teisen Priodas

Summit Height:  338.2m (converted to OSGM15)

Summit Grid Reference:  SN 82014 10832

Bwlch Height:  244.8m (converted to OSGM15)

Bwlch Grid Reference:  SN 84566 11384

Drop:  93.4m


Therefore, the 338.2m LIDAR data produced for the summit position at SN 82014 10832 and the 244.8m LIDAR data produced for the bwlch position at SN 84566 11384 is sufficient for this hill to be classified as a Trichant with 93.4m of drop and for it to be listed with a higher summit than the 296.2m (converted to OSGM15) summit of Mynydd y Drum at SN 80718 09753, with the details from the Trimble GeoXH 6000 survey being 337.9m (converted to OSGM15) summit at SN 82013 10833 and 244.6m (converted to OSGM15) bwlch at SN 84569 11383, giving this hill 93.3m of drop.

This now revises the total in the Y Trichant and the Twmpau which will be updated accordingly.


The full details for the hill are:

Cardinal Hill:  Fan Gyhirych

Summit Height:  337.9m (converted to OSGM15, Trimble data)

Name:  Teisen Priodas

OS 1:50,000 map:  160

Summit Grid Reference:  SN 82013 10833 
  
Drop:  93.3m (converted to OSGM15, Trimble data)


Teisen Priodas (SN 820 108) a new addition to the Y Trichant list

My thanks to Mark Jackson for bringing the details of this hill to my attention and to Kevin McGovern and Aled Williams for their analysis of LIDAR data.


Myrddyn Phillips (March 2017)

Sunday, 26 March 2017

Mapping Mountains – Trimble Surveys – Beacon Hill


09.03.17  Cefn Nedd (SO 185 965)

Cefn Nedd (SO 185 965)

Cefn Nedd forms a neat triangle of land enclosed by minor roads above and to the south-east of the Afon Hafren (River Severn).  The name of Cefn Nedd is more strictly applicable to the uppermost enclosed field where the summit of the hill is situated, with the name deriving from the Tithe map, whilst the name usually given this hill in listings; Goron Ddu, is confirmed from local enquiry to be applicable to the lower slopes of the hill that overlook the Afon Hafren, this is where the name appears on the current Ordnance Survey 1:50,000 Landranger map.

As I parked my car on the side of the road next to the field enclosing the area of the bwlch, a farm vehicle approached, I flagged it down and talked with a local farmer for ten minutes or so, he confirmed where the name of Goron Ddu applied to, and had no objection to me taking a series of data sets in the fields next to the minor road close to the outskirts of Llandyssil.

The first data set I took was close to where the 119m spot height appears on Ordnance Survey maps, to do so I placed the Trimble on the roof of my car and measured a 1.46m offset to the road.  Over the next 90 minutes I took a further five data sets from the area of the bwlch, with the majority of these on the broad valley to valley traverse.  During this process the land remained quiet with just an occasion passing car and a distant farm vehicle chugging up a country lane breaking the silence.

The first data set at the bwlch

The third data set at the bwlch with the village of Llandyssil in the background

The fourth data set at the bwlch

The sixth data set at the bwlch

Packing the Trimble away I walked back toward the car happy in the knowledge that I judged most if not all eventualities for the position of this hill’s critical bwlch had been surveyed. 

As the weather was proving glorious with thick blue skies above and warmth cascading the land, I dispensed with my fleece.  It was a day to savour with the heralding of spring and new growth showing green in hedgerows.

I drove up the lane toward the summit of Cefn Nedd and parked beside the entrance to Coed y Wig.  An old green lane heads toward the hill from here and I followed it to two gates which give access to the upper field.

I passed this beautifully sculptured tree on the ascent of Cefn Nedd

The summit of Cefn Nedd consists of closely cropped grass close to the slopes of a wooded copse, the views northward down the Severn Valley toward Cefn Digoll and the Breiddin are expansive with both floating above the plain below.

Gathering data at the summit of Cefn Nedd

The Trimble set-up position at the summit of Cefn Nedd

After five minutes of summit data were gathered I headed back to the two gates and the old green track, a farm vehicle was approaching the green lane from the field opposite and not wanting to miss an opportunity for place-name research I waved and headed toward it.  I chatted with its occupant; Alan Harding for quite some time, he also confirmed the land where Goron Ddu is situated and gave me a number of names for local hills.

Alan Harding

After thanking Alan for his time it was only a short walk back to my car, on my way down toward it my mind wandered as the greened fields shone in front, a delicate patchwork of curves smoothed with years of grazing and interspersed with bordered and stunted trees giving slight variety to the land.  It had been a good few hours in the sunshine and enthused me to get out again the next day with the Trimble.

A greened patchwork
     

Survey Result:



Summit Height:  207.2m (converted to OSGM15)

Summit Grid Reference:  SO 18524 96503

Bwlch Height:  118.1m (converted to OSGM15)

Bwlch Grid Reference:  SO 19564 95699

Drop:  89.1m (non Subhump status confirmed)

Dominance:  42.99% 

 




Saturday, 25 March 2017

Mapping Mountains – Hill Reclassifications – Yr Uchafion


Fowler’s Arm Chair (SO 041 794) - Double Sub-Uchaf deletion

There has been a reclassification to the listing of Yr Uchafion instigated from analysis of LIDAR data by Aled Williams.  Yr Uchafion is the draft title for a list of the Welsh 500m P15s that takes in all hills in Wales at or above 500m that have a minimum drop of 15m, the list is a joint compilation with Aled Williams, and details relating to this list were published on the Mapping Mountains site in November 2015.

Accompanying the main Yr Uchafion list are three sub lists; 500m Sub-Uchaf, 490m Sub-Uchaf and the Double Sub-Uchaf categories, with the reclassification of this hill affecting the Double Sub-Uchaf hills, with the criteria for inclusion to this sub category being Welsh hills at or above 490m and below 500m in height that have 14m or more and below 15m of drop.

Prior to analysis of LIDAR data by Aled the hill was listed with c 14m of drop based on an estimated summit height of c 491m and the 477m bwlch spot height that appears on the Ordnance Survey enlarged mapping hosted on the Geograph website.

The hill is situated in the Pegwn Mawr group with its Cardinal Hill being Brondre Fawr Hill (SO 041 783) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B1), and is positioned between the small communities of Bwlch y Sarnau towards the south and Llanbadarn Fynydd towards the east south-east.

The hill can be accessed on public footpaths from a number of directions; however its summit is not on open access land, so if wanting to visit its high point permission to do so should be sought.

The name of the hill is Fowler’s Arm Chair and it is the first Double Sub-Uchaf to lose its status since the Yr Uchafion list was announced in November 2015, this is due to the analysis of LIDAR data by Aled.  LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales.

Aled’s analysis of LIDAR data gives the hill the following details:


Fowler’s Arm Chair

Summit Height:  489.5m

Summit Grid Reference:  SO 04122 79426

Bwlch Height:  476.4m

Bwlch Grid Reference:  SO 04192 79062

Drop:  13.1m


Therefore, the 489.5m LIDAR data produced for the summit position at SO 04122 79426 and the 476.4m LIDAR data produced for the bwlch position at SO 04192 79062 gives this hill 13.1m of drop which along with its summit height is insufficient for it to retain its status as a Double Sub-Uchaf.

This now revises the listing of Yr Uchafion which will be updated accordingly and the hill is now deleted from the ranks of Double Sub-Uchaf, with this reclassification appearing in the appropriate Change Register.


The full details for the hill are:

Cardinal Hill:  Brondre Fawr Hill

Summit Height:  489.5m (LIDAR data)

Name:  Fowler’s Arm Chair

OS 1:50,000 map:  136, 147

Summit Grid Reference:  SO 04122 79426   

Drop:  13.1m (LIDAR data)


The reclassifications to the Double Sub-Uchaf category in Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains are ills of wales as follows:



DOUBLE SUB-UCHAF ADDITIONS




DOUBLE SUB-UCHAF DELETIONS

Fowler’s Arm Chair (SO 041 794) Double Sub-Uchaf deleted with 489.5m summit height and 13.1m drop




Myrddyn Phillips and Aled Williams (March 2017)