Friday, 22 September 2017

Mapping Mountains – Hill Reclassifications – Humps


Mynydd Caerau (SS 890 944) – Subhump addition

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

This and forthcoming posts are retrospective as many of these hill reclassifications were initiated from studying the Ordnance Survey enlarged mapping that is hosted on the Geograph website, and for the reclassifications that affected the Humps the email sent to DJM&M was dated 03.10.12 and the details of this hill were then forwarded to Mark Jackson via email on the 04.010.12.

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 reclassification appear below:

There has been a reclassification to the listing of the Humps (HUndred Metre Prominences) due to consulting the Ordnance Survey enlarged mapping that is hosted on the Geograph website, with these details being sent to Mark Jackson on 04.10.12.

Prior to this notification Mark Jackson had listed this hill with c 87m of drop based on the 555m spot height given to a triangulation pillar on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and an estimated bwlch height of c 468m based on bwlch contouring at 10m intervals.  However, with a 464m spot height appearing at the bwlch of this hill on the Ordnance Survey enlarged mapping hosted on the Geograph website it meant that when coupled with the 555m summit height it gave this hill 91m of drop, which is sufficient for it to be classified as a Subhump.  Since this notification LIDAR data has become publicly available and analysis of these data by Aled Williams gives this hill just under the 90m of drop required for Subhump status.

Extract from the Ordnance Survey enlarged mapping hosted on the Geograph website showing the 464m spot height at the bwlch of this hill

The hill is adjoined to the Y Cymoedd range of hills and is situated overlooking the A 4107 road to its north and the A 4064 road towards its south-east, with the small communities of Blaengarw and Pontycymer towards the hill’s south-east and Abergwynfi towards the hill’s north.

The addition of this hill to Subhump status was accepted by Mark Jackson and its new classification augmented in to the listing of the Humps on the 01.12.12.


The full details for the hill are:


Name:  Mynydd Caerau

Summit Height:  555m (as listed in the Humps)

OS 1:50,000 map:  170

OS 1:25,000 map:  166

Summit Grid Reference:  SN 89057 94411 (as listed in the Humps)

Drop:  91 (as listed in the Humps)




Myrddyn Phillips (September 2017)

Thursday, 21 September 2017

Mapping Mountains – Summit Relocations – The 500-Metre Tops of England and Wales


The 500-Metre Tops of England and Wales – Summit Relocations

The 500-Metre Tops of England and Wales are the English, Welsh and Manx hills at or above 500m and below 609.6m (2,000ft) in height that have a minimum drop of 30m.  The list is affectionately known as The Deweys.

The list is authored by Michael Dewey and the posts that have appeared on Mapping Mountains detailing the summit relocations to the list appear below presented chronologically in receding order.








Mapping Mountains - Summit Relocations - The 500-Metre Tops of England and Wales

Esgair Greolen (SN 835 920) - 1st summit relocation

First survey post for Esgair Greolen

Second survey post for Esgair Greolen


Michael Dewey has confirmed that the summit of Bryn yr Ŵyn (SN 83919 92571) is relocated to the higher summit of Esgair Greolen (SN 83574 92022) and therefore replaces Bryn yr Ŵyn as the hill listed in his 500-Metre Tops of England and Wales, which is affectionately known as the Deweys.



My word you’ve been busy in the Pumlumon area. Excellent work and I know it’s going to be appreciated by the people doing the Five-hundreds.  I’m pleased to accept the summit relocations of Bryn yr Ŵyn at grid reference SN 83919 9257 and Esgair Greolen at SN 83574 92022.

Michael Dewey (May 2016)




Esgair Greolen (SN 835 920) centre left of photo and Bryn yr Ŵyn (SN 839 925) on right of photo

The listing to The 500-Metre Tops of England and Wales appeared in Michael’s Mountain tables book which was published by Constable in 1995.  Since that date there have only been a few summit relocations which have resulted in replacement summits being confirmed, those affecting Wales include:


Pen y Bedw East Top (SH 784 470) replaces Pen y Bedw West Top (SH 779 469)

Cerrig Llwydion (SN 909 731) replaces Sychnentydd (SN 909 724)

Esgair Greolen (SN 835 920) replaces Bryn yr Ŵyn (SN 839 925)


Mountain tables by Michael Dewey

This summit relocation and replacement summit was confirmed by a survey conducted over two days; 05.05.16 and 13.05.16 with the Trimble GeoXH 6000.  In all five data sets were taken from the summit of Bryn yr Ŵyn and four from the summit of Esgair Greolen.  Each summit height has been averaged from these combined surveys:


Esgair Greolen 501.4m (converted to OSGM15) summit at SN 83574 92022

Bryn yr Ŵyn 499.9m (converted to OSGM15) summit at SN 83919 92571


Gathering data from the summit of Bryn yr Ŵyn

Gathering data from the summit of Esgair Greolen

If wanting more detail please consult the blog post for the 1st Trimble survey and the 2nd Trimble survey of these summits.  All details relating to each data set taken during the two days which took in these surveys are given in the Trimble Survey Spreadsheet.


Myrddyn Phillips (May 2016)



Tuesday, 19 September 2017

Mapping Mountains – Hill Reclassifications – Y Pedwarau


Waun Sidan (SO 250 726) – 400m Sub-Pedwar reclassified to Pedwar

There has been a reclassification to the listing of Y Pedwarau due to analysis of LIDAR data by Aled Williams.  Y Pedwarau is the title for the list of 400m hills of Wales and takes in all Welsh hills at or 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, with this hill being reclassified from the 400m Sub-Pedwar categoryThe criteria for 400m Sub-Pedwar qualification is all Welsh hills at or above 400m and below 500m in height with 20m or more and below 30m of drop.

Prior to analysis of LIDAR data this hill was listed with 29m of drop based on a basic levelling survey (BLS) conducted by Myrddyn Phillips on the 05.10.03, with the summit height listed as 406m which is taken from the spot height that appears on the Ordnance Survey 1:25,000 Explorer map, based on the map summit height and the BLS these values place the height of the bwlch at 377m.

The name of the hill is Waun Sidan and it is situated in the Maelienydd range of hills with its Cardinal Hill being Bwlch Bank (SO 242 720) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B1).  The hill is positioned above the B 4355 road and the River Teme which are to its north-east, and the A 488 road which is to its south, with the town of Trefyclo (Knighton) towards the east.

As the summit of the hill is not a part of designated open access land permission to visit should be sought, for those wishing to do so the long distance footpath of Glyndŵr’s Way passes just to the south of the summit.

The reclassification of Waun Sidan to Pedwar status is due to the analysis of LIDAR data by Aled Williams.  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:


Waun Sidan

Summit Height:  407.7m

Summit Grid Reference:  SO 25021 72649

Bwlch Height:  376.3m

Bwlch Grid Reference:  SO 24638 72691

Drop:  31.4m


Therefore, the 407.7m LIDAR data produced for the summit position at SO 25021 72649 and the 376.3m LIDAR data produced for the bwlch position at SO 24638 72691 gives this hill 31.4m of drop which is sufficient for it to be classified as a Pedwar.


The full details for the hill are:

Cardinal Hill:  Bwlch Bank 

Summit Height:  407.7m (LIDAR data)

Name:  Waun Sidan

OS 1:50,000 map:  137, 148

Summit Grid Reference:  SO 25021 72649

Drop:  31.4m (LIDAR data)


The total for Y Pedwarau is now 443 hills with ten additions, and fourteen reclassifications to 400m Sub-Pedwar status since publication of the list by Europeaklist in May 2013.

The overall total for the 400m Sub-Pedwarau is now 218 with 27 hills being added and 22 hills being taken out of this category since publication of the list by Europeaklist in May 2013.

The list of Pedwar hills is available from the Haroldstreet website (January 2014) with all subsequent changes detailed on the Mapping Mountains site, with the list also having commenced publication on Mapping Mountains on the 30.01.17.

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











Myrddyn Phillips and Aled Williams (September 2017)


Monday, 18 September 2017

Mapping Mountains – Hill Reclassifications – Humps


Coed-swydd (SO 139 646) – Hump reclassified to Subhump

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

The hill name used in this and forthcoming posts is that used in the listing of Humps, therefore individual names and their composition may not match those that are used in listings I am directly associated with.  However, I am of firm belief that listed hill names used by other authors should be respected when giving detail within other people’s lists, however inappropriate some hill names or their composition may be considered.

This and forthcoming posts are retrospective as many of these hill reclassifications were initiated from studying the Ordnance Survey enlarged mapping that is hosted on the Geograph website, and for the reclassifications that affected the Humps the email I sent to Mark Jackson and copying in the DJM&M team in relation to this hill was dated 02.08.12.

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 reclassification appear below:

There has been a reclassification to the listing of the Humps (HUndred Metre Prominences) due to consulting the Ordnance Survey enlarged mapping that is hosted on the Geograph website, with these details being sent to Mark Jackson on 02.08.12.

Prior to this notification Mark Jackson had listed this hill with c 100m of drop, based on the 412m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps, and an estimated bwlch height of c 312m with its position being incorrectly placed.  However, with a 317m spot height appearing at the bwlch of this hill on the Ordnance Survey enlarged mapping hosted on the Geograph website it meant this hill had less than 100m of drop.  The summit and bwlch height of this hill was examined via Ordnance Survey 1:2,500 mapping with a 1350ft (411.5m) summit height and a 316.3m height at the bwlch confirming this hill has less than 100m of drop.  

Extract from the Ordnance Survey enlarged mapping hosted on the Geograph website showing the 317m spot height on the area of this hill's bwlch

The hill currently appears under the composition of Coed-swydd in the Humps, having previously been listed as Pen Coed-swydd, and it is adjoined to the Elfael group of hills and is situated above the A 488 road which is to its north-west and the A 44 road to its south, with the small communities of Pen-y-bont towards the west south-west and Llandegley towards the south.

The reclassification of this hill from Hump to Subhump status was accepted by Mark Jackson and its new classification augmented in to the listing of the Humps in December 2012.


The full details for the hill are:


Summit Height:  412m (as listed in the Humps)

Name:  Coed-swydd (as listed in the Humps)

OS 1:50,000 map:  148

OS 1:25,000 map:  200

Summit Grid Reference:  SO 13966 64618

Drop:  95m



Myrddyn Phillips (September 2017)






Sunday, 17 September 2017

Mapping Mountains – Summit Relocations – Y Trechol –The Dominant Hills of Wales


Y Trechol –The Dominant Hills of Wales – Summit Relocations

Y Trechol –The Dominant Hills of Wales are the Welsh P30 hills whose prominence equal or exceed half that of their absolute height, accompanying the Dominant list is a sub list entitled The Lesser Dominant Hills of Wales with the criteria for this sub category being those additional Welsh P30 hills whose prominence is between one third and half that of their absolute height.  The list commenced publication on Mapping Mountains on 03.012.15 with its Introduction giving details to its compilation and criteria, with Change Registers also created for the Dominant and the Lesser Dominant category.

The list is authored by Myrddyn Phillips and the posts that have appeared on Mapping Mountains detailing the summit relocations to the Dominant and Lesser Dominant list appear below presented chronologically in receding order.








Y Trechol - The Dominant Hills of Wales - Summit Relocations

Pen y Berth (SJ 081 127) - 2nd summit relocation

Summit survey post for Pen y Berth

Bwlch survey post for Pen y Berth

Significant Height Revisions post for Pen y Bwlch
  

There has been a Summit Relocation to the Y Trichant - The Dominant Hills of Wales list and also the 200m Twmpau (thirty welsh metre prominences and upward) list due to a survey with the Trimble GeoXH 6000, and these details are retrospective as the survey that resulted in this summit relocation was conducted on 19th October 2014.

The survey was conducted in the hills just to the east of the small community of Dolanog, with the hill positioned above the B4382 which is to its south, and above the Afon Efyrnwy which is to its north.

The hill was surveyed in the company of Mark Trengove on a day when the westerly showers were being pushed east; thankfully all missed us as we visited two hills over two separate walks.

The hill is named Pen y Berth, and its prioritised summit position was listed at SJ 080 127 as this is where its 282m summit spot height appears on the Ordnance Survey enlarged mapping hosted on the Geograph website.  This map also shows a twin 282m map heighted summit at SJ 083 127.

The position of the spot height at SJ 080 127 is immersed in a conifer plantation, whilst the position of the spot height at SJ 083 127 is on open ground with small deciduous trees growing near to it.  The latter position was surveyed with the Trimble GeoXH 6000 as was a position on the periphery of the conifer plantation that was visually higher than the remaining ground within the forestry.


The result of each survey appears below:


282m spot height at SJ 083 127 came to 283.7m (converted to OSGM15) at SJ 08322 12748

new summit position came to 287.5m (converted to OSGM15) at SJ 08126 12730

282m spot height at SJ 080 127 was not surveyed as its position was deemed lower compared to the new summit position


The position of the relocated summit is at SJ 08126 12730 and is the top of featureless ground under Larch trees, this is not given a spot height on current Ordnance Survey maps but the Trimble result gave it as 5.5m higher and approximately 80 metres eastward from where the westerly 282m map spot height is positioned on the ground.


The full details for the hill are:

Cardinal Hill:  Carreg y Big

Summit Height:  287.5m (converted to OSGM15)

Name:  Pen y Berth

OS 1:50,000 map:  125

Summit Grid Reference (New Position):  SJ 08126 12730 

Drop:  134.2m (converted to OSGM15)

Dominance:  46.68%


The Trimble GeoXH 6000 set up at the new summit position of Pen y Berth, with the old position of the prioritised summit approximately 80 metres behind the Trimble and further into the conifer plantation

For details on the survey that relocated the summit of this hill please click {here}

Myrddyn Phillips (October 2014)






Y Trechol - The Dominant Hills of Wales - Summit Relocations

Graig Wen (SH 397 947) - 1st summit relocation

Survey post for Graig Wen


There has been a Summit Relocation to the listing of Y Trechol - The Dominant Hills of Wales, with the hill also listed in the 30-99m Twmpau (thirty welsh metre prominences and upward).  This is the first post under this heading and the summit relocation was initiated by a survey with the Trimble GeoXH 6000 with the following details being retrospective as the Trimble survey that resulted in this summit relocation was conducted on 7th September 2014.

The survey was conducted in the north of Ynys Môn on a fine and bright day on a grouping of three excellent hills in the company of Alex Cameron, with the hill situated north-eastward of the small town of Cemaes, with the nearest major road to the hill being the A 5025 which is 1km directly south of its summit.

The name of the hill is Graig Wen, and its summit position used to be listed beside its trig pillar on a small rock outcrop at SH 398 947 which is within a small continuous 90m ring contour on current Ordnance Survey maps.

Its new summit position is approximately 80 metres westward from its trig pillar and is the top of a large boulder which is prominent when approaching the hill from the west.  This position has no uppermost 90m ring contour given it on current Ordnance Survey maps.


The full details for the hill are:

Cardinal Hill:  Mynydd Twr

Summit Height:  91.3m (converted to OSGM15)

Name:  Graig Wen

OS 1:50,000 map:  114

Summit Grid Reference (New Position):  SH 39734 94739 
  
Drop:  c 48m

Dominance:  52.58%


The Trimble GeoXH 6000 gathering data at the new summit position of Graig Wen, with the old position for the summit next to the hill's trig pillar in the background on the left of the photo

For details on the survey that relocated the summit of this hill please click {here}


Myrddyn Phillips (September 2014)

Saturday, 16 September 2017

Mapping Mountains – Hill Reclassifications – Humps


Fan (SN 672 316) – Subhump addition

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

This and forthcoming posts are retrospective as many of these hill reclassifications were initiated from studying the Ordnance Survey enlarged mapping that is hosted on the Geograph website, and for the reclassifications that affected the Humps the email I posted on the RHB Yahoo Group forum in relation to this hill was dated 28.05.12.

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 reclassification appear below:

There has been a reclassification to the listing of the Humps (HUndred Metre Prominences) due to consulting the Ordnance Survey enlarged mapping that is hosted on the Geograph website, with these details being posted on the RHB Yahoo Group forum on 28.05.12.

Prior to this notification Mark Jackson had listed this hill with c 89m of drop based on the 265m spot height given to a triangulation pillar on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and an estimated bwlch height of c 176m based on bwlch contouring at 10m intervals.  The summit area of this hill has two uppermost 260m contour rings with the easterly one being where the 265m trig pillar is positioned, whilst the westerly one is given a 267m summit spot height on the Ordnance Survey enlarged mapping hosted on the Geograph website, this when coupled with an estimated bwlch height of 174m – 175m gives this hill sufficient drop for it to be classified as a Subhump.

Extract from the Ordnance Survey 1:25,000 Explorer map showing the 265m spot height adjoined to the trig pillar on the eastern 260m contour ring

Extract from the Ordnance Survey enlarged mapping hosted on the Geograph website showing the 267m summit spot height on the western 260m ring contour

The hill is adjoined to the Mynydd Mallaen group of hills and is situated overlooking the Afon Tywi (River Towy) and the village of Llangadog to its south-east and the village of Llanwrda to its east.

The addition of this hill to Subhump status was accepted by Mark Jackson and its new classification augmented in to the listing of the Humps on the 19.07.12.


The full details for the hill are:


Name:  Fan

Summit Height:  267

OS 1:50,000 map:  146

OS 1:25,000 map:  12, 186

Summit Grid Reference:  SN 67221 31601

Drop:  c 92 (as listed in the Humps)


Myrddyn Phillips (September 2017)