Friday, 16 June 2017

Mapping Mountains – Hill Reclassifications – The Welsh 500m P15s (Yr Uchafion)


The Welsh 500m P15s (Yr Uchafion) – Hill Reclassifications

The Welsh 500m P15s are the Welsh hills at or above 500m in height that have a minimum drop of 15m.  Accompanying the main P15 list are three sub lists; these are the 500m Subs, 490m Subs and the Double Subs with their criteria detailed in the respective Change Registers which are linked in their above titles, with details to this list given in the Introduction that was published on Mapping Mountains in November 2015. 

The list is co-authored by Myrddyn Phillips and Aled Williams and the posts that have appeared on Mapping Mountains detailing the additions, reclassifications and deletions to the main P15 list and the sub lists appear below presented chronologically in receding order.







Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Cefn Wylfre (SO 145 510) – 490m Sub-Uchaf addition (27th reclassification)


There has been an addition 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 in height that have a minimum drop of 15m, the list is a joint compilation between Myrddyn Phillips and Aled Williams with the introduction to the list being published on Mapping Mountains in November 2015.

Accompanying the main Yr Uchafion list are three sub lists; 500m Sub-Uchaf490m Sub-Uchaf and the Double Sub-Uchaf categories, with the addition of this hill affecting the 490m Sub-Uchaf category, with the criteria for inclusion to this sub category being all Welsh hills at or above 490m and below 500m in height that have a minimum 15m of drop.

Prior to analysis of LIDAR data this hill was not classified as its estimated drop was c 15m based on its 489m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated bwlch height of c 474m based on bwlch contouring between 470m – 480m.

The hill is situated in the Elfael group of hills with its Cardinal Hill being Glascwm Hill (SO 169 525) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B1), with the small communities of Glascwm towards the north north-east, Hundred House towards the north-west and Cregrina towards the west north-west.

The hill is a part of designated open access land and for those wishing to visit there are a number of tracks leading toward the hill from the west and the south, and it can also be combined with its higher neighbours if wanting a longer walk.

The name of the hill is Cefn Wylfre and its addition to the 490m Sub-Uchaf category 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:


Cefn Wylfre

Summit Height:  490.1m

Summit Grid Reference:  SO 14585 51034

Bwlch Height:  474.9m

Bwlch Grid Reference:  SO 14819 51062

Drop:  15.2m


Therefore, the 490.1m LIDAR data produced for the summit position at SO 14585 51034 and the 474.9m LIDAR data produced for the bwlch position at SO 14819 51062 gives this hill 15.2m of drop which when coupled with its height is sufficient for it to be classified as a 490m Sub-Uchaf.


The full details for the hill are:

Cardinal Hill:  Glascwm Hill

Summit Height:  490.1m (LIDAR data)

Name:  Cefn Wylfre

OS 1:50,000 map:  148

Summit Grid Reference:  SO 14585 51034  
Drop:  15.2m (LIDAR data)


The overall total for Yr Uchafion / The Welsh 500m P15s remains at 631 hills with the total for the 490m Sub-Uchaf category increasing by one to 63 hills.

For the additions, reclassifications and deletions to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains please consult the following Change Registers:










Myrddyn Phillips and Aled Williams (October 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Carreg yr Ast (SN 877 591) – 500m Sub-Uchaf addition (26th reclassification)


There has been an addition 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 in height that have a minimum drop of 15m, the list is a joint compilation between Myrddyn Phillips and Aled Williams with the introduction to the list being published on Mapping Mountains in November 2015.

Accompanying the main Yr Uchafion list are three sub lists; 500m Sub-Uchaf490m Sub-Uchaf and the Double Sub-Uchaf categories, with the addition of this hill affecting the 500m Sub-Uchaf category, with the criteria for inclusion to this sub category being all Welsh hills at or above 500m in height that have 14m or more and below 15m of drop.

Prior to analysis of LIDAR data the hill was not classified as its estimated drop was c 13m based on its 579m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and an estimated bwlch height of c 566m based on bwlch contouring between 560m – 570m.

The hill is situated in the Elenydd group of hills with its Cardinal Hill being Drygarn Fawr (SN 862 584) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B2), and in Welsh terms the hill is a long way away from any small community.

The hill is a part of designated open access land and for those wishing to visit it can be combined with Drygarn Fawr and Gorllwyn which gives a rewarding walk on the high summits of the Elenydd, with easiest access from the north.

The name of the hill is Carreg yr Ast and its addition to the 500m Sub-Uchaf category 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:


Carreg yr Ast

Summit Height:  579.2m

Summit Grid Reference:  SN 87717 59184

Bwlch Height:  564.3m

Bwlch Grid Reference:  SN 87743 58937

Drop:  14.9m


Therefore, the 579.2m (579.23m) LIDAR data produced for the summit position at SN 87717 59184 and the 564.3m (564.29m) LIDAR data produced for the bwlch position at SN 87743 58937 gives this hill 14.9m (14.94m) of drop which is sufficient for it to be classified as 500m Sub-Uchaf.


The full details for the hill are:

Cardinal Hill:  Drygarn Fawr

Summit Height:  579.2m (LIDAR data)

Name:  Carreg yr Ast

OS 1:50,000 map:  147

Summit Grid Reference:  SN 87717 59184  
Drop:  14.9m (LIDAR data)


The overall total for Yr Uchafion / The Welsh 500m P15s remains at 631 hills with the total for the 500m Sub-Uchaf category increasing by one to 26 hills.

For the additions, reclassifications and deletions to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains please consult the following Change Registers:










Myrddyn Phillips and Aled Williams (July 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Banc Steffan (SN 833 700) – 500m Sub-Uchaf deletion (25th reclassification)


There has been a deletion from 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 in height that have a minimum drop of 15m, the list is a joint compilation between Myrddyn Phillips and Aled Williams with the introduction to the list being published on Mapping Mountains in November 2015.

Accompanying the main Yr Uchafion list are three sub lists; 500m Sub-Uchaf490m Sub-Uchaf and the Double Sub-Uchaf categories, with the deletion of this hill affecting the 500m Sub-Uchaf category, with the criteria for inclusion to this sub category being all Welsh hills at or above 500m in height that have 14m or more and below 15m of drop.

Prior to analysis of LIDAR data the hill was listed with 14m of drop which was sufficient for it to be included as a 500m Sub-Uchaf.  This drop value was based on a basic levelling survey (BLS) conducted by Myrddyn Phillips. 

To explain the process of the BLS and as the land where Banc Steffan is situated has three individual summits, with each separated by a bwlch, it is wise to list their details from north to south that appear on the Ordnance Survey 1:25,000 Explorer map:


Summit 1 – Cnapyn Drawsffos (SN 83443 70638) 549m

Bwlch 1 – 530m – 540m (SN 83371 70383)

Summit 2 – Banc Steffan (SN 83359 70024) no spot height with 540m uppermost contour ring

Bwlch 2 – 530m – 540m (SN 83222 69403)

Summit 3 – Cefn Ffosyrewig (SN 83242 69234) 549m


The BLS resulted in 46ft 6˝ (14.2m) of drop and was conducted from Bwlch 1 to summit 1 (Cnapyn Drawsffos) and as Summit 1 and Summit 3 both have 549m spot heights the BLS survey meant that whichever was lower in height would qualify as a 500m Sub-Uchaf.  However, as LIDAR data gives Cnapyn Drawsffos as higher than Banc Steffan, and Banc Steffan higher than Cefn Ffosyrewig, it is Banc Steffan that would have been listed as a 500m Sub-Uchaf.

The hill is situated in the Elenydd group of hills with its Cardinal Hill being Carn yr Hyrddod (SN 790 704) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B2), and in Welsh terms the hill is a long way away from any small community.

The hill is one of the remotest situated from any paved public road in Wales, therefore an ascent is likely to be a long affair, with an ascent from the east north-east following the old Monks Trod being possibly the best option.  However, much of the higher Elenydd is open country and has enjoyed unrestricted access for many years and an ascent from most directions will be fulfilling, albeit a bit wild.

The name of the hill is Banc Steffan and its deletion from the 500m Sub-Uchaf category 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 distinguished Banc Steffan to be higher than Cefn Ffosyrewig and gives the hill the following details:


Banc Steffan

Summit Height:  548.0m

Summit Grid Reference:  SN 83359 70024

Bwlch Height:  534.2m

Bwlch Grid Reference:  SN 83371 70383

Drop:  13.8m


Therefore, the 548.0m LIDAR data produced for the summit position at SN 83359 70024 and the 534.2m LIDAR data produced for the bwlch position at SN 83371 70383 gives this hill 13.8m of drop which is insufficient for it to retain its status as a 500m Sub-Uchaf.


The full details for the hill are:

Cardinal Hill:  Carn yr Hyrddod

Summit Height:  548.0m (LIDAR data)

Name:  Banc Steffan

OS 1:50,000 map:  135, 136, 147

Summit Grid Reference:  SN 83359 70024 
  
Drop:  13.8m (LIDAR data)


The overall total for Yr Uchafion / The Welsh 500m P15s remains at 631 hills with the total for the 500m Sub-Uchaf category remains at 25.  This figure remains at it was prior to this hill's deletion as the hill was missed from this sub category when the Introduction to the list was published on Mapping Mountains in November 2015.

For the additions, reclassifications and deletions to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains please consult the following Change Registers:










Myrddyn Phillips and Aled Williams (May 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Banc yr Ŵyn (SN 771 923) – Double Sub-Uchaf deletion (24th reclassification)


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 in height that have a minimum drop of 15m, the list is a joint compilation between Myrddyn Phillips and 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-Uchaf490m Sub-Uchaf and the Double Sub-Uchaf categories, with the reclassification of this hill affecting the Double Sub-Uchaf category, 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 the 491m summit spot height that appears on the Ordnance Survey enlarged mapping hosted on the Geograph website and an estimated bwlch height of c 477m based on bwlch contouring between 470m – 480m.

The hill is situated in the Pumlumon group with its Cardinal Hill being Pen y Darren (SN 764 942) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B2), and in Welsh terms it is a long way away from any small community.

As the hill is immersed in conifer plantation a route to its summit cannot be advised, although if wanting to visit waiting for the trees to be felled may be the most sensible and easiest option.

The name of the hill is Banc yr Ŵyn and its deletion from the ranks of Double Sub-Uchaf 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 for the bwlch (summit not covered) gives the hill the following details:


Banc yr Ŵyn

Summit Height:  491m

Summit Grid Reference:  SN 77182 92335

Bwlch Height:  478.1m

Bwlch Grid Reference:  SN 77031 92373

Drop:  13m


Therefore, the 491m summit spot height at SN 77182 92335 and the 478.1m LIDAR data produced for the bwlch position at SN 77031 92373 gives this hill 13m of drop which is insufficient for it to retain its status as a Double Sub-Uchaf.


The full details for the hill are:

Cardinal Hill:  Pen y Darren

Summit Height:  491m

Name:  Banc yr Ŵyn

OS 1:50,000 map:  135

Summit Grid Reference:  SN 77182 92335 
  
Drop:  13m (OS summit spot height and LIDAR bwlch data)


The overall total for Yr Uchafion / The Welsh 500m P15s is now 631 hills with the total for the Double Sub-Uchaf category now being 5.

For the additions, reclassifications and deletions to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains please consult the following Change Registers:











Myrddyn Phillips and Aled Williams (May 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Foel Wyddon (SN 788 836) - Uchaf addition (23rd reclassification)


There has been a new addition to the ranks 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 in height that have a minimum drop of 15m, the list is a joint compilation between Myrddyn Phillips and Aled Williams, with the details relating to this list being published on the Mapping Mountains site in November 2015.

This hill is given a 535m summit spot height on Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps and has bwlch contouring between 520m – 530m, with an estimated drop based on these map figures of c 13m which is insufficient for qualification as an Uchaf, and therefore prior to the analysis of LIDAR data the hill was not classified.

The hill is adjoined to the Pumlumon group of hills with its Cardinal Hill being Pumlumon Fawr (SN 789 869) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B2), and is situated with the small community of Ponterwyd to its south-west.

The hill is positioned on designated open access land and can be easily accessed via a public footpath on a track from Eisteddfa Gurig which is to the east north-east of the summit.

The name of the hill is Foel Wyddon and its addition to Uchaf status is due to 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:


Foel Wyddon

Summit Height:  535.9m (converted to OSGM15)

Summit Grid Reference:  SN 78812 83668

Bwlch Height:  520.9m (converted to OSGM15)

Bwlch Grid Reference:  SN 78784 83859

Drop:  15.0m


Therefore, the 535.9m (converted to OSGM15) LIDAR data produced for the summit position at SN 78812 83668 and the 520.9m (converted to OSGM15) LIDAR data produced for the bwlch position at SN 78784 83859 gives this hill 15.0m of drop, which is sufficient for it to be classified as an Uchaf.


The full details for the hill are:

Cardinal Hill:  Pumlumon Fawr

Summit Height:  535.9m (converted to OSGM15) (LIDAR data)

Name:  Foel Wyddon

OS 1:50,000 map:  135

Summit Grid Reference:  SN 78812 83668 
  
Drop:  15.0m (converted to OSGM15) (LIDAR data)


The overall total for Yr Uchafion / The Welsh 500m P15s is now 631 hills with the total for the 500m Sub-Uchaf category remaining at 25.

For the additions, reclassifications and deletions to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains please consult the following Change Registers:










Foel Wyddon (SN 788 836) now added as an Uchaf.  Photo: Aled Williams

Myrddyn Phillips and Aled Williams (May 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Bwlan (SH 946 255) - Uchaf deletion (22nd reclassification)

Survey post for Bwlan

Significant Height Revisions post for Bwlan


There has been a deletion from the listing of Yr Uchafion instigated from analysis of LIDAR data by Aled Williams and subsequently confirmed via a survey with the Trimble GeoXH 6000.  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 between Myrddyn Phillips and Aled Williams, with details relating to this list being published on the Mapping Mountains site in November 2015.

Accompanying the main Yr Uchafion list are three sub lists; 500m Sub-Uchaf490m Sub-Uchaf and the Double Sub-Uchaf categories, with the deletion of this hill affecting the main P15 Yr Uchafion list.

Prior to analysis of LIDAR data the hill was listed with 16m of drop based on a 51ft 6˝ (15.7m) basic levelling survey conducted my Myrddyn Phillips on the 10.05.05.  The hill is given a 528m summit spot height on Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps and has a 514m bwlch spot height on the Ordnance Survey enlarged mapping hosted on the Geograph website.  There are two options for where the critical bwlch of this hill is placed and between each is a 523m map heighted bump, the spot height on the enlarged map on the Geograph website appears on the eastern side of this bump and this is where the basic levelling survey started from, with the alternate westerly bwlch being visually dismissed as higher.  However, the basic levelling survey was conducted to the top of the 523m map heighted bump and not to the summit of the 528m map heighted Bwlan, this survey came to 10.7m, and 5m was then added to the drop value to compensate for the difference in map heights.  To ascertain a drop value for a hill using this method is not ideal and the accuracy and therefore this hill’s qualification as an Uchaf was always open to question.

The hill is situated in the Y Berwyn group of hills with its Cardinal Hill being Foel y Geifr (SH 918 246) and is placed in the Region of North Wales (Region A, Sub-Region A4), and is positioned between the stream valleys of the Afon Nadroedd to the north and the Afon Eiddew to the south, with Llyn Efyrnwy (Lake Vyrnwy) towards the hill’s south-east.

The hill is situated on open access land and can be accessed from the north either by following the boundary of a conifer plantation to cross the Nant Nadroedd Fawr before following a track to the hill’s bwlch, or it can be ascended starting lower in the valley from where the same track leaves the minor road and heads through the conifer plantation.  As the latter route through the conifer plantation is not on open access land permission to use this route should be sought.

The name of the hill is Bwlan and its deletion from Uchaf 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:


Bwlan

Summit Height:  526.1m (converted to OSGM15)

Summit Grid Reference:  SH 94690 25541

Bwlch Height:  512.6m (converted to OSGM15)

Bwlch Grid Reference:  SH 94180 25715

Drop:  13.6m


Therefore, the 526.1m (converted to OSGM15) LIDAR data produced for the summit position at SH 94690 25541 and the 512.6m (converted to OSGM15) LIDAR data produced for the bwlch position at SH 94180 25715 gives this hill 13.55m of drop which is insufficient for its retention as an Uchaf and also for it to be reclassified as a 500m Sub-Uchaf, with the details from the Trimble GeoXH 6000 survey being 525.9m (converted to OSGM15) summit at SH 94692 25540 and 512.1m (converted to OSGM15) bwlch at SH 94179 25714, giving this hill 13.8m of drop. 


The full details for the hill are:

Cardinal Hill:  Foel y Geifr

Summit Height:  525.9m (converted to OSGM15, Trimble data)

Name:  Bwlan

OS 1:50,000 map:  125

Summit Grid Reference:  SH 94692 25540 
  
Drop:  13.8m (converted to OSGM15, Trimble data)


The overall total for Yr Uchafion / The Welsh 500m P15s is now 63o hills with the total for the 500m Sub-Uchaf category remaining at 25.

For the additions, reclassifications and deletions to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains please consult the following Change Registers:










Bwlan (SH 946 255) confirmed as a deleted Uchaf

Myrddyn Phillips and Aled Williams (April 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Pt. 522.0m (SJ 136 363) - 500m Sub-Uchaf deletion (21st reclassification)


There has been a deletion from 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 between Myrddyn Phillips and Aled Williams, with details relating to this list being published on the Mapping Mountains site in November 2015.

Accompanying the main Yr Uchafion list are three sub lists; 500m Sub-Uchaf490m Sub-Uchaf and the Double Sub-Uchaf categories, with the deletion of this hill affecting the 500m Sub-Uchaf classification, with the criteria for qualification to this sub category being all Welsh hills at or above 500m in height that have 14m or more and below 15m of drop.

Prior to analysis of LIDAR data the hill was listed with 14m of drop based on the 522m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps and the 508m bwlch spot height that appears on the Ordnance Survey 1:25,000 Explorer map.

The hill is situated in the Y Berwyn group of hills with its Cardinal Hill being Moel Fferna (SJ 116 397) and is placed in the Region of North Wales (Region A, Sub-Region A4), and is positioned with the small communities of Llanarmon Dyffryn Ceiriog to its south south-east and Pandy to its east.

The hill is situated on open access land and can be accessed from the south or north-east, with public footpaths making their way up to higher ground from the stream valleys containing the Afon Ceiriog and the Afon Teirw respectively.

Although a number of local names for the hill exist it is being catalogued by the point (Pt. 522.0m) notation and its deletion from the 500m Sub-Uchaf category 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:


Pt. 522.0m

Summit Height:  522.0m (converted to OSGM15)

Summit Grid Reference:  SJ 13615 36369

Bwlch Height:  508.2m (converted to OSGM15)

Bwlch Grid Reference:  SJ 13888 36062

Drop:  13.8m


Therefore, the 522.0m (converted to OSGM15) LIDAR data produced for the summit position at SJ 13615 36369 and the 508.2m (converted to OSGM15) LIDAR data produced for the bwlch position at SJ 13888 36062 gives this hill 13.8m of drop which is insufficient for its retention as a 500m Sub-Uchaf.


The full details for the hill are:

Cardinal Hill:  Craig Berwyn

Summit Height:  522.0m (converted to OSGM15) (LIDAR data)

Name:  Pt. 522.0m

OS 1:50,000 map:  125

Summit Grid Reference:  SJ 13615 36369
   
Drop:  13.8m (converted to OSGM15) (LIDAR data)


The overall total for Yr Uchafion / The Welsh 500m P15s remains at 631 hills with the total for the 500m Sub-Uchaf category now being 25

For the additions, reclassifications and deletions to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains please consult the following Change Registers:










Myrddyn Phillips and Aled Williams (April 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Blaen yr Henbant (SO 254 217) - Double Sub-Uchaf addition (20th reclassification)


There has been an addition 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-Uchaf490m Sub-Uchaf and the Double Sub-Uchaf categories, with the addition of this hill affecting the Double Sub-Uchaf classification, with the criteria for inclusion to this sub category being all 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 the hill was catalogued with 12m of drop based on the 498m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps and the 486m bwlch spot height that appears on the Ordnance Survey enlarged mapping hosted on the Geograph website.

The hill is situated in the Mynyddoedd Duon (Black Mountains) group of hills with its Cardinal Hill being Waun Fach (SO 215 299) and is placed in the Region of South Wales (Region C, Sub-Region C3), and is positioned between the town of Crucywel (Crickhowell) to the south-west and the small community of Forest Coal Pit to the east south-east.

The hill can be accessed via a bridleway from its south-west that forms a part of the Beacons Way, or from public footpaths towards the south and north-east.  However, the hill is positioned at the end of one of this hill ranges extended ridges and a two car walk taking in the full length of this ridge ending on the summit of Blaen yr Henbant is highly recommended.

The name of the hill is Blaen yr Henbant and its inclusion as a Double Sub-Uchaf 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:


Blaen yr Henbant

Summit Height:  497.8m (converted to OSGM15)

Summit Grid Reference:  SO 25412 21736

Bwlch Height:  483.0m (converted to OSGM15)

Bwlch Grid Reference:  SO 25537 22004

Drop:  14.8m


Therefore, the 497.8m (converted to OSGM15) LIDAR data produced for the summit position at SO 25412 21736 and the 483.0m (converted to OSGM15) LIDAR data produced for the bwlch position at SO 25537 22004 gives this hill 14.8m of drop and when combined with its summit height is sufficient for the hill to be included as a Double Sub-Uchaf.


The full details for the hill are:

Cardinal Hill:  Waun Fach

Summit Height:  497.8m (converted to OSGM15) (LIDAR data)

Name:  Blaen yr Henbant

OS 1:50,000 map:  161

Summit Grid Reference:  SO 25412 21736
   
Drop:  14.8m (converted to OSGM15) (LIDAR data)


The overall total for Yr Uchafion / The Welsh 500m P15s remains at 631 hills with the total for the Double Sub-Uchaf category now being 6.

For the additions, reclassifications and deletions to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains please consult the following Change Registers:










Myrddyn Phillips and Aled Williams (April 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Pt. 524.0m (SN 881 163) - 500m Sub-Uchaf addition (19th reclassification)


There has been an addition 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, with the details relating to this list being published on the Mapping Mountains site in November 2015.

The listing of Yr Uchafion includes three sub lists; the 500m Sub-Uchaf490m Sub-Uchaf and the Double Sub-Uchaf category.  This hill has been included as a 500m Sub-Uchaf, with the criteria for this classification being all Welsh hills at or above 500m in height that have 14m or more and below 15m of drop.

This hill is given a 524m summit spot height on the Ordnance Survey 1:25,000 Explorer map and has bwlch contouring between 510m – 520m, implying that it has insufficient drop to be considered for the 500m Sub-Uchaf category.

The hill is adjoined to the Fforest Fawr group of hills 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 situated with the small community of Glyntawe to its west.

The hill can be accessed via public footpaths from Penwyllt towards its west, or from towards its south-east from the end of a minor road that heads north following the course of the Nedd Fechan.

As the authors do not know either a local or historical name that is appropriate for the hill the point (Pt. 524m) notation is being used, and its inclusion as a 500m Sub-Uchaf is due to 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:


Pt. 524m

Summit Height:  524.0m (converted to OSGM15)

Summit Grid Reference:  SN 88113 16370

Bwlch Height:  509.4m (converted to OSGM15)

Bwlch Grid Reference:  SN 87908 16298

Drop:  14.6m


Therefore, the 524.0m (converted to OSGM15) LIDAR data produced for the summit position at SN 88113 16370 and the 509.4m (converted to OSGM15) LIDAR data produced for the bwlch position at SN 87908 16298 gives this hill 14.6m of drop, which is sufficient for its inclusion as a 500m Sub-Uchaf


The full details for the hill are:

Cardinal Hill:  Fan Gyhirych

Summit Height:  524.0m (converted to OSGM15) (LIDAR data)

Name:  Pt. 524.0m

OS 1:50,000 map:  160

Summit Grid Reference:  SN 88113 16370 
  
Drop:  14.6m (converted to OSGM15) (LIDAR data)


The overall total for Yr Uchafion / The Welsh 500m P15s remains at 631 hills with the total for the 500m Sub-Uchaf category now being 26.

For the additions, reclassifications and deletions to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains please consult the following Change Registers:










Myrddyn Phillips and Aled Williams (April 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Moel Bowydd (SH 712 470) - Uchaf addition (18th reclassification)

Survey post for Moel Bowydd

Significant Height Revisions post for Moel Bowydd


There has been a new addition to the ranks of Yr Uchafion instigated from analysis of LIDAR data by Aled Williams and subsequently confirmed via a survey with the Trimble GeoXH 6000.  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, with the details relating to this list being published on the Mapping Mountains site in November 2015.

This hill is given an uppermost 490m ring contour with no spot height on current Ordnance Survey maps and has bwlch contouring between 480m – 490m, and prior to the analysis of LIDAR data the hill was not classified.

The hill is adjoined to the Arennig group of hills with its Cardinal Hill being Manod Mawr (SH 724 446) and is placed in the Region of North Wales (Region A, Sub-Region A3), and is situated with the town of Blaenau Ffestiniog to the south-west and is positioned above the Afon Bowydd which is to its south and which emanates from Llyn Bowydd which is to the east of the hill.

The hill can be accessed via public footpaths from its west, east and south, with Blaenau Ffestiniog being a good starting point for an ascent; an alternate and longer ascent can start from above Llan Ffestiniog using a track beside the course of the Afon Teigl.  However, the summit of this hill is not on open access land, therefore permission should be sought to visit, but as the summit is relatively close to a public footpath and with open access land to its immediate north, common sense should prevail and if wanting to visit the summit of the hill there is likely to be no objection to doing so.

The name of the hill is Moel Bowydd and its addition to Uchaf status is due to 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:


Moel Bowydd

Summit Height:  500.6m

Summit Grid Reference:  SH 71276 47053

Bwlch Height:  c 485m

Bwlch Grid Reference:  SH 71586 47206

Drop:  c 16m


Although the area of the bwlch is not covered by LIDAR data, 1m contouring shows that the bwlch is lower than 485m, which gives this hill sufficient drop to qualify as an Uchaf.  Therefore, the 500.6m LIDAR data produced for the summit position at SH 71276 47053 and with 1m bwlch contouring showing that the height of the bwlch is below 485m, giving this give a drop of more than 15m, with the details from the Trimble GeoXH 6000 survey being 500.5m (converted to OSGM15) summit at SH 71272 47051 and 482.4m (converted to OSGM15) bwlch at SH 71603 47208, giving this hill 18.1m of drop


The full details for the hill are:

Cardinal Hill:  Manod Mawr

Summit Height:  500.5m (converted to OSGM15, Trimble data)

Name:  Moel Bowydd

OS 1:50,000 map:  115

Summit Grid Reference:  SH 71272 47051
   
Drop:  18.1m (converted to OSGM15, Trimble data)


This now brings the overall total for Yr Uchafion / The Welsh 500m P15s to 631 hills with the overall total for the 500m Sub-Uchaf category remaining at 25.

The additions, reclassifications and deletions to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains are as follows:



UCHAF ADDITIONS







Moel Bowydd (Trimble data) (SH 71272 47051) added as an Uchaf with 18.1m of drop





500m SUB UCHAF RECLASSIFICATIONS TO UCHAF






UCHAF RECLASSIFICATIONS TO 500m SUB-UCHAF










UCHAF RECLASSIFICATIONS TO 490m SUB-UCHAF






UCHAF DELETIONS





Moel Bowydd (SH 712 470) is now classified as an Uchaf

Myrddyn Phillips and Aled Williams (April 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Drum Boeth (SH 717 464) - Uchaf addition (17th reclassification)

Survey post for Drum Boeth


There has been a new addition to the ranks of Yr Uchafion instigated from analysis of LIDAR data by Aled Williams and subsequently confirmed via a survey with the Trimble GeoXH 6000.  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, with the details relating to this list being published on the Mapping Mountains site in November 2015.

This hill is given an uppermost 500m ring contour with no spot height on current Ordnance Survey maps and has bwlch contouring between 490m – 500m, and prior to the analysis of LIDAR data the hill was not classified.

The hill is adjoined to the Arennig group of hills with its Cardinal Hill being Manod Mawr (SH 724 446) and is placed in the Region of North Wales (Region A, Sub-Region A3).  The hill is situated with the town of Blaenau Ffestiniog to the west south-west and is positioned above the small mountain lake of Llyn y Drum Boeth which is to its east.

The hill can be accessed via a public footpath from Blaenau Ffestiniog and can be combined with its namesake and also newly crowned Uchaf which is positioned at SH 72020 46289, an alternate and longer ascent can start from above Llan Ffestiniog using a track beside the course of the Afon Teigl.  However, the summit of this hill is not on open access land and it is positioned on the periphery of quarry spoil, therefore permission should be sought to visit, but as the summit is relatively close to a public footpath and with open access land to its north, east and south, common sense should prevail and if wanting to visit the summit there is likely to be no objection to doing so.

The name of the hill is Drum Boeth and its addition to Uchaf status is due to 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:


Drum Boeth

Summit Height:  506.6m

Summit Grid Reference:  SH 71721 46419

Bwlch Height:  490.5m

Bwlch Grid Reference:  SH 71821 46454

Drop:  16.1m


Therefore, the 506.6m LIDAR data produced for the summit position at SH 71721 46419 and the 490.5m LIDAR data produced for the bwlch position at SH 71821 46454 gives this hill 16.1m of drop, which is sufficient for its addition to Uchaf status, with the details from the Trimble GeoXH 6000 survey being 506.8m (converted to OSGM15) summit at SH 71724 46417 and 490.4m (converted to OSGM15) bwlch at SH 71823 46452, giving this hill 16.4m of drop


The full details for the hill are:

Cardinal Hill:  Manod Mawr

Summit Height:  506.8m (converted to OSGM15, Trimble data)

Name:  Drum Boeth

OS 1:50,000 map:  115

Summit Grid Reference:  SH 71721 46419 
  
Drop:  16.4m (converted to OSGM15, Trimble data)


This now brings the overall total for Yr Uchafion / The Welsh 500m P15s to 630 hills with the overall total for the 500m Sub-Uchaf category remaining at 25.

The additions, reclassifications and deletions to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains are as follows:



UCHAF ADDITIONS






Drum Boeth (LIDAR data and Trimble survey) (SH 71724 46417) added as an Uchaf with 16.4m of drop





500m SUB UCHAF RECLASSIFICATIONS TO UCHAF






UCHAF RECLASSIFICATIONS TO 500m SUB-UCHAF










UCHAF RECLASSIFICATIONS TO 490m SUB-UCHAF






UCHAF DELETIONS





Drum Boeth (SH 717 464) confirmed via LIDAR data and a Trimble survey as an Uchaf

Myrddyn Phillips and Aled Williams (April 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Drum Boeth (SH 720 462) - 500m Sub-Uchaf reclassified to Uchaf (16th reclassification)

Survey post for Drum Boeth


There has been a reclassification to the listing of Yr Uchafion instigated from analysis of LIDAR data by Aled Williams and subsequently confirmed via a survey with the Trimble GeoXH 6000.  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, with the details relating to this list being published on the Mapping Mountains site in November 2015.

The listing of Yr Uchafion includes three sub lists; the 500m Sub-Uchaf490m Sub-Uchaf and the Double Sub-Uchaf category.  The reclassification of this hill is from 500m Sub-Uchaf to Uchaf, with the criteria for 500m Sub-Uchaf status being all Welsh hills at or above 500m in height that have 14m or more and below 15m of drop.

This hill is given an uppermost 520m ring contour with no spot height on current Ordnance Survey maps and has bwlch contouring between 500m – 510m, and prior to the analysis of LIDAR data the hill was listed as a 500m Sub-Uchaf based on a basic levelling survey conducted by Myrddyn Phillips on the 27th October 2005, which resulted in a drop value of 48ft 6˝ (14.8m) which was insufficient for it to qualify for Uchaf status.

The hill is adjoined to the Arennig group of hills with its Cardinal Hill being Manod Mawr (SH 724 446) and is placed in the Region of North Wales (Region A, Sub-Region A3).  The hill is situated with the town of Blaenau Ffestiniog to the west south-west and is positioned between the small mountain lakes of Llyn y Drum Boeth to the north-west and Llyn Du Bach to the south.

The hill can be accessed via a track that follows the course of the Afon Teigl from above Llan Ffestiniog or via public footpaths from Blaenau Ffestioniog, however current mapping shows that the summit of the hill is not on open access land, although being close to it, and on a previous visit the land between each is open and unfenced and therefore hard to distinguish where the open access land ends, in situations like this common sense should prevail and if wanting to visit the summit there is likely to be no objection to doing so.

The name of the hill is Drum Boeth and its reclassification from 500m Sub-Uchaf to Uchaf is due to 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:


Drum Boeth

Summit Height:  523.4m

Summit Grid Reference:  SH 72020 46289

Bwlch Height:  508.3m

Bwlch Grid Reference:  SH 72161 46335

Drop:  15.1m


Therefore, the 523.4m LIDAR data produced for the summit position at SH 72020 46289 and the 508.3m LIDAR data produced for the bwlch position at SH 72161 46335 gives this hill 15.1m of drop, which is sufficient for its reclassification to Uchaf status, with the details from the Trimble GeoXH 6000 survey being 523.4m (converted to OSGM15) summit at SH 72020 46289 and 508.1m (converted to OSGM15) bwlch at SH 72159 46335, giving this hill 15.2m of drop


The full details for the hill are:

Cardinal Hill:  Manod Mawr

Summit Height:  523.4m (LIDAR data and Trimble data [converted to OSGM15])

Name:  Drum Boeth

OS 1:50,000 map:  115

Summit Grid Reference:  SH 72020 46289
   
Drop:  15.2m (LIDAR and Trimble summit data and Trimble bwlch data [converted to OSGM15])


This now brings the overall total for Yr Uchafion / The Welsh 500m P15s to 629 hills with the overall total for the 500m Sub-Uchaf category now being 25.

The additions, reclassifications and deletions to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains are as follows:



UCHAF ADDITIONS










500m SUB UCHAF RECLASSIFICATIONS TO UCHAF

Drum Boeth (LIDAR data) (SH 720 462) 500m Sub-Uchaf reclassified to Uchaf with 15.2m of drop





UCHAF RECLASSIFICATIONS TO 500m SUB-UCHAF










UCHAF RECLASSIFICATIONS TO 490m SUB-UCHAF






UCHAF DELETIONS





The Trimble GeoXH 6000 gathering data at the summit of Drum Boeth (SH 720 462)

Myrddyn Phillips and Aled Williams (April 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Fowler’s Arm Chair (SO 041 794) - Double Sub-Uchaf deletion (15th reclassification)


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-Uchaf490m 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 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)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Pt. 499.1m (SN 863 760) - Uchaf reclassified to 490m Sub-Uchaf (14th reclassification)


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, with the details relating to this list being published on the Mapping Mountains site in November 2015.

The listing of Yr Uchafion includes three sub lists; the 500m Sub-Uchaf490m Sub-Uchaf and the Double Sub-Uchaf category.  The reclassification of this hill is from Uchaf to 490m Sub-Uchaf, this sub category takes in the hills at or above 490m and below 500m in height that have 20m or more and below 30m of drop.

The hill is situated in the Elenydd group of hills with its Cardinal Hill being Draws Drum (SN 790 811) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B2).  The hill is situated with the small community of Llangurig to the north-east and Cwmystwyth to the west south-west and is positioned directly above and to the north of the narrow mountain road that heads north-westward from Rhaeadr Gwy (Rhayader).

The hill can be accessed relatively easily from the minor road to its west south-west, from where a public footpath is indicated on Ordnance Survey maps heading up the stream valley to the hill’s west, from here the ascent is on relatively easy grass to a flat topped summit.

The hill was previously listed as an Uchaf and given an estimated height of c 500m based on the flatness of its summit area in relation to the small uppermost 500m contour ring that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map.

The name of the hill is currently being listed by the point (Pt. 499.1m) notation until this list is published and its reclassification from Uchaf to 490m Sub-Uchaf is due to 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:


Pt. 499.1m

Summit Height:  499.1m

Summit Grid Reference:  SN 86343 76073

Bwlch Height:  471.0m

Bwlch Grid Reference:  SN 86323 76358

Drop:  28.1m


Therefore, the 499.1m LIDAR data produced for the summit position at SN 86343 76073 and the 471.0m LIDAR data produced for the bwlch position at SN 86323 76358 gives this hill 28.1m of drop, which is in good accordance with the value produced for this hill when surveyed by John Barnard, Graham Jackson, David Purchase and myself in June 2008 using a level and staff resulting in a drop of 27.9m.  Therefore the summit height of this hill is insufficient for it to retain its Uchaf status. 


The full details for the hill are:

Cardinal Hill:  Draws Drum

Summit Height:  499.1m (LIDAR data)

Name:  Pt. 499.1m

OS 1:50,000 map:  135, 136, 147

Summit Grid Reference:  SN 86343 76073 
  
Drop:  27.9m (line survey)


This now brings the overall total for Yr Uchafion / The Welsh 500m P15s to 628 hills with the overall total for the 500m Sub-Uchaf category remaining at 26, and the 490m Sub-Uchaf total increasing by one to 62.

The additions, reclassifications and deletions to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains are as follows:



UCHAF ADDITIONS









UCHAF RECLASSIFICATIONS TO 500m SUB-UCHAF









UCHAF RECLASSIFICATIONS TO 490m SUB-UCHAF

Pt. 499.1m (SN 863 760) Uchaf reclassified to 490m Sub-Uchaf with 499.1m summit height




UCHAF DELETIONS




Myrddyn Phillips and Aled Williams (March 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Blaen y Clawdd Du (SN 878 752) - Uchaf addition (13th reclassification)


There has been a new entry 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.  Details relating to this list were published on the Mapping Mountains site in November 2015.

The listing of Yr Uchafion includes three sub lists; the 500m Sub-Uchaf490m Sub-Uchaf and the Double Sub-Uchaf category.  The classification of this hill is from unclassified to Uchaf, as the hill was previously catalogued with insufficient drop even to attain 500m Sub-Uchaf status.

The hill is situated in the Elenydd group of hills with its Cardinal Hill being Draws Drum (SN 790 811) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B2).  The hill is situated with the small community of Llangurig to the north-east and is positioned between the stream valleys of the Afon Elan to the south and the Nant y Trafel Gwyn which flows into the Nant y Dernol to the east.

The hill can be accessed from a forestry road to its north, although this may require a bit of tree bashing to reach its high point unless the track is left for open hillside at the northerly connecting bwlch, or it can be accessed from the south-west where a narrow mountain road gives the opportunity of starting the ascent from approximately 390m high.

The hill was previously catalogued with 13m of drop and therefore thought of as being unclassified, this value was based on detail from Ordnance Survey maps, with the 1:50,000 Landranger, the 1:25,000 Explorer and the enlarged map hosted on the Geograph website all giving a summit spot height of 517m, with the latter map also giving a bwlch spot height of 504m.

The name of the hill is Blaen y Clawdd Du and its classification as an Uchaf is due to 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:


Blaen y Clawdd Du

Summit Height:  516.8m

Summit Grid Reference:  SN 87845 75282

Bwlch Height:  501.2m

Bwlch Grid Reference:  SN 87916 75115

Drop:  15.6m


Therefore, the 516.8m LIDAR data produced for the summit position at SN 87845 75282 and the 501.2m LIDAR data produced for the bwlch position at SN 87916 75115 gives this hill 15.6m of drop which is sufficient for it to be included as an Uchaf  as its drop value is more than the minimum of 15m required.


The full details for the hill are:

Cardinal Hill:  Draws Drum

Summit Height:  516.8m (LIDAR data)

Name:  Blaen y Clawdd Du

OS 1:50,000 map:  135, 136, 147

Summit Grid Reference:  SN 87845 75282 
  
Drop:  15.6m (LIDAR data)


This now brings the overall total for Yr Uchafion / The Welsh 500m P15s to 629 hills with the overall total for the 500m Sub-Uchaf category remaining at 26.

The additions, reclassifications and deletions to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains are as follows:



UCHAF ADDITIONS





Blaen y Clawdd Du (LIDAR data) (SN 878 752) added as an Uchaf with 15.6m of drop




UCHAF RECLASSIFICATIONS









UCHAF DELETIONS




Myrddyn Phillips and Aled Williams (February 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Cefn Cwm Coel (SN 891 647) - Uchaf reclassified to 500m Sub-Uchaf (12th reclassification)


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.  Details relating to this list were published on the Mapping Mountains site in November 2015.

The listing of Yr Uchafion includes three sub lists; the 500m Sub-Uchaf490m Sub-Uchaf and the Double Sub-Uchaf category.  The reclassification of this hill is from Uchaf to 500m Sub-Uchaf, with the criteria for this sub category being all Welsh hills at or above 500m in height that have 14m or more and below 15m of drop.

The hill is situated in the Elenydd group of hills with its Cardinal Hill being Carn yr Hyrddod (SN 790 704) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B2).  The hill is situated with the small community of the Elan Village to its east and is positioned above the Claerwen Reservoir to its west and the Graig-ddu Reservoir to its east.

The hill can be accessed from its east south-east, starting from a picnic place where a public footpath heads west through conifer and then deciduous woodland contouring round the south-western part of the Graig-ddu Reservoir.  A track then leads up the lower slopes of the hill to open access land and a faint path marked on the Ordnance Survey 1:25,000 Explorer map then heads toward the summit.

The hill was listed as an Uchaf with 15m of drop which is the minimum required for inclusion in the main list, this was based on detail from Ordnance Survey maps, with the 1:50,000 Landranger, the 1:25,000 Explorer and the enlarged map hosted on the Geograph website all giving a summit spot height of 504m, with the latter map also giving a bwlch spot height of 489m.

The name of the hill is Cefn Cwm Coel and its reclassification from an Uchaf to a 500m Sub-Uchaf is due to 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.  As LIDAR data does not cover this hill’s summit, only the bwlch data can be analysed.

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


Cefn Cwm Coel

Summit Height:  504m

Summit Grid Reference:  SN 89101 64730

Bwlch Height:  489.6m (LIDAR data)

Bwlch Grid Reference:  SN 88436 65371

Drop:  14m (LIDAR data for bwlch)


Therefore, the 504m summit spot height on Ordnance Survey maps at SN 89101 64730 and the 489.6m LIDAR data produced for the bwlch position at SN 88436 65371 gives this hill 14m of drop which is insufficient for it to retain its Uchaf status as its drop is below the minimum of 15m required.


The full details for the hill are:

Cardinal Hill:  Carny yr Hyrddod

Summit Height:  504m

Name:  Cefn Cwm Coel

OS 1:50,000 map:  147

Summit Grid Reference:  SN 89101 64730 
  
Drop:  14m (LIDAR data for bwlch)


This now brings the overall total for Yr Uchafion / The Welsh 500m P15s to 628 hills and the overall total for the 500m Sub-Uchaf category to 26.

The additions, reclassifications and deletions to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains are as follows:



UCHAF ADDITIONS








UCHAF RECLASSIFICATIONS





Cefn Cwm Coel (LIDAR data for bwlch) (SN 891 647) Uchaf reclassified to 500m Sub-Uchaf with 14m of drop




UCHAF DELETIONS




Myrddyn Phillips and Aled Williams (February 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Pen Maen Wern (SN 864 620) - Uchaf deletion (11th reclassification)


There has been a deletion 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.  Details relating to this list were published on the Mapping Mountains site in November 2015.

The listing of Yr Uchafion includes three sub lists; the 500m Sub-Uchaf490m Sub-Uchaf and the Double Sub-Uchaf category.  The deletion of this hill is from Uchaf to unclassified as it has insufficient drop to qualify for the 500m Sub-Uchaf category.

The hill is situated in the Elenydd group of hills with its Cardinal Hill being Drygarn Fawr (SN 862 584) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B2).  The hill is situated with the small community of the Elan Village to its north north-east and is positioned above the Claerwen Reservoir to its north and the Caban-coch Reservoir to its east.

The hill can be accessed from its east where a track heads up onto its lower slopes from the end of a minor road that makes its way to the farm buildings named Rhiwnant.  A narrow path leaves this track and heads westward toward the standing stone atop the 505m map heighted summit at SN 881 613.  From here it is less than 2km to the summit of Pen Maen Wern.

The hill was listed as an Uchaf based on a rudimentary levelling survey conducted by Myrddyn Phillips on 26.06.05 which gave the hill 50ft (15.2m) of drop.  However, the hill’s inclusion in this list was dependent upon its prominence being taken to the top of the standing stone that adorns its summit, as the drop value from its connecting bwlch to ground at the base of the ancient monolith was measured as being 45ft (13.7m), with the height of the standing stone measured as being 5ft (1.52m) high.  Therefore this hill’s inclusion as an Uchaf was dependent upon the height of the ancient standing stone being taken into account.  As this stone has been in situ for over 2,000 years it is considered permanent in nature and therefore it is considered as being a part of the hill.

The name of the hill is Pen Maen Wern and its deletion as an Uchaf 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:


Pen Maen Wern

Summit Height:  543.2m

Summit Grid Reference:  SN 86433 62011

Bwlch Height:  529.9m

Bwlch Grid Reference:  SN 85875 61850

Drop:  13.3m


Therefore, the 543.2m LIDAR data produced for the summit position at SN 86433 62011 and the 529.9m LIDAR data produced for the bwlch position at SN 85875 61850 gives this hill 13.3m of drop which is insufficient for it to retain its Uchaf status as its drop is below the minimum of 15m required.


The full details for the hill are:

Cardinal Hill:  Drygarn Fawr

Summit Height:  543.2m (LIDAR data)

Name:  Pen Maen Wern

OS 1:50,000 map:  147

Summit Grid Reference:  SN 86433 62011 
  
Drop:  13.3m (LIDAR data)



This now brings the overall total for Yr Uchafion / The Welsh 500m P15s to 629 hills with the overall total for the 500m Sub-Uchaf category remaining at 25.

The additions, reclassifications and deletions to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains are as follows:



UCHAF ADDITIONS








UCHAF RECLASSIFICATIONS








UCHAF DELETIONS


Pen Maen Wern (LIDAR data) (SN 864 620) Uchaf deletion with 13.3m of drop


Myrddyn Phillips and Aled Williams (February 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Cefn Onneu (SO 171 156) - Uchaf reclassified to 500m Sub-Uchaf (10th reclassification)


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.  Details relating to this list were published on the Mapping Mountains site in November 2015.

The listing of Yr Uchafion includes three sub lists; the 500m Sub-Uchaf490m Sub-Uchaf and the Double Sub-Uchaf category.  The reclassification of this hill is from Uchaf to 500m Sub-Uchaf, with the criteria for this sub category being all Welsh hills at or above 500m in height that have 14m or more and below 15m of drop.

The hill is situated in the Bannau Brycheiniog (Brecon Beacons) group of hills with its Cardinal Hill being Pen y Fan (SO 012 215) and is placed in the Region of South Wales (C-2).  The hill is situated between the villages of Llangynidr to its north north-west, Cendl (Beaufort) to its south and Llangatwg to its east north-east.

The hill was listed with c 15m of drop which is the minimum drop value for inclusion as an Uchaf, with a c 530m summit based on a small uppermost 530m ring contour on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps, and an estimated bwlch height of c 515m based on bwlch contouring between 510m – 520m.

The name of the hill is Cefn Onneu and it can be easily accessed from its west as the B 4560 passes within 0.7km of its summit, and its reclassification from an Uchaf to a 500m Sub-Uchaf 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:


Cefn Onneu

Summit Height:  530.0m

Summit Grid Reference:  SO 17112 15692

Bwlch Height:  515.6m

Bwlch Grid Reference:  SO 16549 15819

Drop:  14.4m


Therefore, the 530.0m LIDAR data produced for the summit position at SO 17112 15692 and the 515.6m LIDAR data produced for the bwlch position at SO 16549 15819 gives this hill 14.4m of drop which is insufficient for it to retain its Uchaf status as its drop is below the required minimum of 15m.


The full details for the hill are:

Cardinal Hill:  Pen y Fan

Summit Height:  530.0m (LIDAR data)

Name:  Cefn Onneu

OS 1:50,000 map:  161

Summit Grid Reference:  SO 17112 15692 
  
Drop:  14.4m (LIDAR data)


This now brings the overall total for Yr Uchafion / The Welsh 500m P15s to 630 hills and the overall total for the 500m Sub-Uchaf category to 25.

The additions, reclassifications and deletions to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains are as follows:



UCHAF ADDITIONS









UCHAF RECLASSIFICATIONS





Cefn Onneu (LIDAR data) (SO 171 156) Uchaf reclassified to 500m Sub-Uchaf with 14.4m of drop




UCHAF DELETIONS




Myrddyn Phillips and Aled Williams (January 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Twynau Gwynion (SO 067 106) - 490m Sub-Uchaf reclassified to Double Sub-Uchaf (9th reclassification)


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.  Details relating to this list were published on the Mapping Mountains site in November 2015.  The status change affects the 490m Sub-Uchaf list with a hill being reclassified to a Double Sub-Uchaf, these are the hills at or above 490m and below 500m in height that have 14m or more and below 15m of drop.

The hill is situated in the Bannau Brycheiniog (Brecon Beacons) group of hills with its Cardinal Hill being Pen y Fan (SO 012 215) and is placed in the Region of South Wales (Region C, Sub-Region C2).  The hill is situated between the small community of Pontsticill to its north-west and the town of Merthyr Tudful to its south.

Current Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer mapping has a 498m summit spot height for this hill, with a previously listed drop value of 16m based on the 482m bwlch spot height that appears on the Ordnance Survey enlarged mapping hosted on the Geograph website.

The hill can be accessed from a public footpath that approaches it from Pontsticill to the north-west or from a track to the south that leads to the disused Twynau Gwynion Quarries which are situated just below the summit of the hill to its west.

The name of the hill is Twynau Gwynion and it is the first 490m Sub-Uchaf to be reclassified to a Double Sub-Uchaf, and its inclusion in the latter category 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:


Twynau Gwynion

Summit Height:  496.2m

Summit Grid Reference:  SO 06765 10699

Bwlch Height:  481.3m

Bwlch Grid Reference:  SO 06781 10855

Drop:  14.9m


Therefore, the 496.2m LIDAR data produced for the summit position at SO 06765 10699 and the 481.3m LIDAR data produced for the bwlch position at SO 06781 10855 gives this hill 14.9m of drop which is insufficient for it to retain its status as a 490m Sub-Uchaf.

This now revises the total in Yr Uchafion which will be updated accordingly and the hill is now listed as a Double Sub-Uchaf.


The full details for the hill are:

Cardinal Hill:  Pen y Fan

Summit Height:  496.2m (LIDAR data)

Name:  Twynau Gwynion

OS 1:50,000 map:  160

Summit Grid Reference:  SO 06765 10699
   
Drop:  14.9m (LIDAR data)


The reclassifications to the 490m Sub-Uchaf category in Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains are as follows:



490m SUB-UCHAF RECLASSIFICATIONS

Twynau Gwynion (SO 067 106) 490m Sub-Uchaf reclassified to Double Sub-Uchaf with 14.9m of drop.


Myrddyn Phillips and Aled Williams (January 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Cwar yr Ystrad (SO 082 140) - Uchaf addition (8th reclassification)


There has been a new addition 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.  Details relating to this list were published on the Mapping Mountains site in November 2015.

The hill is situated in the Bannau Brycheiniog (Brecon Beacons) group of hills with its Cardinal Hill being Pen y Fan (SO 012 215) and is placed in the Region of South Wales (C-2).  The hill is a part of the Cwar yr Ystrad quarry and this is where it takes its name from and its qualification as an Uchaf is partly due to quarrying that has taken place over past years, the hill is situated between the Pentwyn and Pontsticill Reservoirs to its west and the Talybont Reservoir to its north north-east, with the town of Merthyr Tudful to its south south-west and the small community of Trefil to its east south-east.

Current Ordnance Survey 1:50,000 and 1:25,000 mapping does not give this hill any ring contours, as is the norm for areas of land that have been quarried.  The hill is of interest as it is only now listed as an Uchaf through the quarrying activities of past years that has resulted in producing a new bwlch for the hill.

The hill can be accessed from public footpaths that approach it from a number of directions, whilst one of the most convenient routes is via the paved road north of Trefil that gives access onto the track that makes its way up to the quarry, but if wishing to ascend from this direction it should be noted that there is a barrier across the road beyond Trefil that is locked at 5.00pm and unlocked at 6.30am with online write ups stating this barrier is locked at weekends.

The name of the hill is Cwar yr Ystrad and it should be noted that this is the second new Uchaf hill to be announced recently that is listed under the same name, with the first new Uchaf hill listed as Cwar yr Ystrad being positioned at SO 08358 14245, and its inclusion as an Uchaf 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, and as mentioned in the first paragraph of this post; if Cwar yr Ystrad has a minimum of 15m of drop it would be included in the listing of Welsh hills at or over 500m in height that has a minimum of 15m of drop, and has the working title of Yr Uchafion.

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


Cwar yr Ystrad

Summit Height:  572.8m

Summit Grid Reference:  SO 08216 14087

Bwlch Height:  555.3m

Bwlch Grid Reference:  SO 07952 13652

Drop:  17.5m


Therefore, the 572.8m LIDAR data produced for the summit position at SO 08216 14087 and the 555.3m LIDAR data produced for the bwlch position at SO 07952 13652 gives this hill 17.5m of drop which is sufficient for it to be classified as an Uchaf.

This now revises the total in Yr Uchafion which will be updated accordingly and the hill is now listed as an Uchaf.


The full details for the hill are:

Cardinal Hill:  Pen y Fan

Summit Height:  572.8m (LIDAR data)

Name:  Cwar yr Ystrad

OS 1:50,000 map:  160

Summit Grid Reference:  SO 08216 14087 
  
Drop:  17.5m (LIDAR data)


The reclassifications to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains are as follows:


UCHAF ADDITIONS




Cwar yr Ystrad (LIDAR data) (SO 082 140) added as an Uchaf with 17.5m of drop.




UCHAF RECLASSIFICATIONS







UCHAF DELETIONS



Myrddyn Phillips and Aled Williams (January 2017)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Cwar yr Ystrad (SO 083 142) - Uchaf addition (7th reclassification)


There has been a new addition 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.  Details relating to this list were published on the Mapping Mountains site in November 2015.

The hill is situated in the southern part of the Bannau Brycheiniog (Brecon Beacons) group of hills with its Cardinal Hill being Pen y Fan (SO 012 215) and is placed in the Region of South Wales (C-2).  As its name suggests the hill is a part of a quarry with its qualification as an Uchaf partly due to past quarry activities, it is situated between the Pentwyn and Pontsticill Reservoirs to its west and the Talybont Reservoir to its north north-east, with the town of Merthyr Tudful to its south south-west and the small community of Trefil to its east south-east.

Current Ordnance Survey 1:50,000 and 1:25,000 mapping does not give this hill any ring contours, as is the norm for areas of land that have been quarried.  The hill is of interest as it is only now listed as an Uchaf through the quarrying activities of past years that has resulted in producing a new bwlch for the hill.

The hill can be accessed from a number of directions on public footpaths including from its south-west and from its north, whilst the route from the paved road north of Trefil also gives access onto the quarry track, but if wishing to ascend from this direction it should be noted that there is a barrier across the road beyond Trefil that is locked at 5.00pm and unlocked at 6.30am with online write ups stating this barrier is locked at weekends.

The name of the hill is Cwar yr Ystrad and its inclusion as an Uchaf 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, and as mentioned in the first paragraph of this post; if Cwar yr Ystrad has a minimum drop of 15m it would be included in the listing of Welsh hills at or over 500m in height that has a minimum of 15m of drop, and has the working title of Yr Uchafion.

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


Cwar yr Ystrad

Summit Height:  579.9m

Summit Grid Reference:  SO 08358 14245

Bwlch Height:  558.9m

Bwlch Grid Reference:  SO 08376 14189

Drop:  21.0m


Therefore, the 579.9m LIDAR data produced for the summit position at SO 08358 14245 and the 558.9m LIDAR data produced for the bwlch position at SO 08376 14189 is sufficient for this hill to be classified as an Uchaf with 21.0m of drop.

This now revises the total in Yr Uchafion which will be updated accordingly and the hill is now listed as an Uchaf.


The full details for the hill are:

Cardinal Hill:  Pen y Fan

Summit Height:  579.9m (LIDAR data)

Name:  Cwar yr Ystrad

OS 1:50,000 map:  160

Summit Grid Reference:  SO 08358 14245 
  
Drop:  21.0m (LIDAR data)


The reclassifications to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains are as follows:


UCHAF ADDITIONS



Cwar yr Ystrad (LIDAR data) (SO 083 142) added as an Uchaf with 21.0m of drop.




UCHAF RECLASSIFICATIONS







UCHAF DELETIONS



Myrddyn Phillips and Aled Williams (January 2017)







Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Esgair y Llyn (SN 841 701) - Uchaf addition (6th reclassification)


There has been a new addition to the listing of Yr Uchafion instigated from map study and confirmed from LIDAR data analysed 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 of 15m of drop, the list is a joint compilation with Aled Williams.  Details relating to this list were published on the Mapping Mountains site in November 2015.

The hill is situated in the Elenydd group of hills in the central part of Mid and West Wales.  This grouping of hills forms one of the wildest in Wales and takes in some of the most remote hills in the country.  The hill is situated in an immense grassland of moor and tussocks with Llyn Cerrigllwydion Isaf to its south-east and the higher summits of Cnapyn Drawsffos (SN 834 706) to its north-west and Blaen Rhestr (SN 843 693) towards its south.  Any towns or villages are a far distance away with Ysbyty Ystwyth towards the west and Rhaeadr Gwy (Rhayader) towards the east.

The hill can be accessed from its north-east via a track that leads to the farmhouse of Glanhirin, a path then leads toward and up the north-eastern ridge of Blaen Rhestr.  However, an alternate route would be using the Monks Trod, which is an ancient route across the hills developed by the Cistercian monks as a bi-way between the abbeys of Cwm-Hir and Strata Florida.  Whichever way is chosen it leads into land that is open and somewhat featureless.

The name of the hill is Esgair y Llyn and its inclusion as an Uchaf was spotted by Aled as the Ordnance Survey enlarged mapping on the Geograph website gives this hill a 529m summit spot height and a 513m bwlch spot height, this 16m of drop is sufficient to enter the list of Uchafion. 

As Aled was analysing other hills in the vicinity against LIDAR data, he did likewise with Esgair y Llyn.  LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales, and as mentioned in the first paragraph of this post; if Esgair y Llyn has a minimum of 15m of drop it would be included in the listing of Welsh hills at or over 500m in height that has a minimum of 15m of drop, and has the working title of Yr Uchafion.

Aled’s analysis of LIDAR data gave the hill a 528.8m summit height at SN 84118 70177, and a 513.3m bwlch height at SN 83811 70087, these values give this hill 15.5m of drop which is sufficient for qualification as an Uchaf.

This now revises the total in Yr Uchafion which will be updated accordingly and the hill is now listed as an Uchaf.


The full details for the hill are:

Cardinal Hill:  Carn yr Hyrddod

Summit Height:  528.8m (LIDAR data)

Name:  Esgair y Llyn

OS 1:50,000 map:  135, 136, 147

Summit Grid Reference:  SN 84118 70177 
  
Drop:  15.5m (LIDAR data)



The reclassifications to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains are as follows:



UCHAF ADDITIONS


Esgair y Llyn (LIDAR data) (SN 841 701) added as an Uchaf with 15.5m of drop.



UCHAF RECLASSIFICATIONS




UCHAF DELETIONS



Myrddyn Phillips and Aled Williams (December 2016)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Pt. 637.1m (SO 267 322) - Uchaf reclassifed to 500m Sub-Uchaf (5th reclassification)

Survey post for Pt. 637.1m


There has been a reclassification to the listing of Yr Uchafion instigated from analysis of LIDAR data by Aled Williams and subsequently confirmed via a survey with the Trimble GeoXH 6000.  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 of 15m of drop, the list is a joint compilation with Aled Williams.  Details relating to this list were published on the Mapping Mountains site in November 2015.

The hill is situated in the Mynyddoedd Duon (Black Mountains) group of hills in the eastern part of the Parc Cenedlaethol Bannau Brycheiniog (Brecon Beacons National Park) in the Region of South Wales (C-3) and is situated on the most easterly of the main elongated ridges of this hill range with Waun Fach (SO 215 299) being its Cardinal Hill, and it is positioned above the small community of Capel-y-ffin to its south-west and the Olchon Valley to its east and the Vale of Ewyas to its south.  The hill can be accessed on good paths from these two valleys or from its south-east or north-west via the Offa’s Dyke Path that follows the ridge crest.

As an appropriate name for this hill is not in the public domain it is being listed under the point (Pt. 637.1m) notation, and its reclassification from an Uchaf to a 500m Sub-Uchaf is due to the analysis of LIDAR data.  LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales, and the hill was first analysed with this data by Joseph Nuttall, independent of this, Aled also analysed LIDAR data using a slightly different method and ascertained the details for this hill’s reclassification.

If Pt. 637.1m does not have the minimum of 15m of drop it would be taken out of the listing of Welsh hills at or over 500m in height that has a minimum of 15m of drop, and has the working title of Yr Uchafion, and if having between 14m and below 15m of drop the hill would be classified as a 500m Sub-Uchaf.

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


Pt. 637.4m

Summit Height:  637.4m (converted to OSGM15, and middle of three equivalent height points)

Summit Grid Reference:  SO 26696 32273

Bwlch Height:  622.7m (converted to OSGM15)

Bwlch Grid Reference:  SO 26711 32628

Drop:  14.7m


As the stated philosophy for our co-authored lists is to take the most accurate data available on any given day, and as Ordnance Survey map data uses a 637m summit spot height attained from an aerial survey that has a prescribed margin of uncertainty of +/- 3m applicable to it and as the previously listed bwlch height is based on contour interpolation, it is viewed that LIDAR data is sufficient to reclassify this hill as it is quoted as having a prescribed margin of uncertainty of +/- 0.15m. 

Therefore, the 637.4m LIDAR data produced for the summit position at SO 26696 32273 and the 622.7m LIDAR data produced for the bwlch position at SO 26711 32628 is insufficient for this hill to retain its Uchaf status, with the details from the Trimble GeoXH 6000 survey being 637.1m (converted to OSGM15) summit at SO 26709 32261 and also SO 26695 32273 and 622.5m (converted to OSGM15) bwlch at SO 26710 32627, and therefore with 14.5m of drop Pt. 637.1m is reclassified to a 500m Sub-Uchaf.

This now revises the total in Yr Uchafion which will be updated accordingly and the hill is now listed as a 500m Sub-Uchaf.


The full details for the hill are:

Cardinal Hill:  Waun Fach

Summit Height:  637.1m (converted to OSGM15)

Name:  Pt. 637.1m

OS 1:50,000 map:  161

Summit Grid Reference:  SO 26709 32261 
  
Drop:  14.5m (converted to OSGM15)


The reclassifications to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains are as follows:


UCHAF ADDITIONS




UCHAF RECLASSIFICATIONS



Pt. 637.1m (SO 267 322) Uchaf reclassified to 500m Sub-Uchaf with 14.5m of drop.



UCHAF DELETIONS




Pt. 637.1m (SO 267 322) is now reclassified from an Uchaf to a 500m Sub-Uchaf

Myrddyn Phillips and Aled Williams (November 2016)






Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)


Carnedd y Ddelw (SH 708 705) - Uchaf deletion (4th reclassification)


There has been a deletion to the listing of Yr Uchafion instigated from analysis of LIDAR data by Aled Williams, and subsequently confirmed via a line survey for drop and a Leica GS15 survey for height conducted by John Barnard and Graham Jackson.  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 of 15m of drop, the list is a joint compilation with Aled Williams.  Details relating to this list were published on the Mapping Mountains site in November 2015.

The hill is situated in the Carneddau group of hills in the northern part of the Parc Cenedlaethol Eryri (Snowdonia National Park) in the Region of North Wales and is situated directly northward of Drum (SH 708 695) with Carnedd Llywelyn being its Cardinal Hill, and it is positioned above the town of Llanfairfechan to its north north-west and the small community of Tal-y-bont to its east south-east.

The hill can be easily accessed from its north-east from the car park at the end of the narrow lane that makes its way to the top of Bwlch y Ddeufaen.  This car park is situated at SH 720 715 and enables an ascent of the hill from the convenience of a starting point of around 420m in height.  The hill can also be combined with its higher neighbours to the south or the lower peaks to its north-west.

The name of the hill is Carnedd y Ddelw and its deletion as an Uchaf 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, and as mentioned in the first paragraph of this post; if Carnedd y Ddelw does not have the minimum of 15m of drop it would be deleted from the listing of Welsh hills at or over 500m in height that has a minimum of 15m of drop, and has the working title of Yr Uchafion.

Aled’s analysis of LIDAR data gives the hill a 685.6m summit height at SH 70810 70531, and a 672.0m bwlch height at SH 70873 70344, these values give this hill 13.6m of drop which is insufficient for qualification as an Uchaf.

The LIDAR data analysed by Aled has a prescribed margin of uncertainty of +/- 0.15m, whilst the Ordnance Survey 688m summit height and 673m bwlch height each have a prescribed margin of uncertainty of +/- 3m.

This now revises the total in Yr Uchafion which will be updated accordingly and the hill is now deleted as an Uchaf.


The full details for the hill are:

Cardinal Hill:  Carnedd Llywelyn

Summit Height:  686.0m (Leica GS15 data)

Name:  Carnedd y Ddelw

OS 1:50,000 map:  115

Summit Grid Reference:  SH 70814 70535 
  
Drop:  13.97m (Line Survey)



The reclassifications to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains are as follows:


UCHAF ADDITIONS




UCHAF RECLASSIFICATIONS





UCHAF DELETIONS

Carnedd y Ddelw (LIDAR data) (SH 708 705) Uchaf deletion with 13.97m of drop.


Carnedd y Ddelw (SH 708 705) now deleted from the listing of Yr Uchafion

Myrddyn Phillips and Aled Williams (November 2016)







Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Craig Gwaun Taf (SO 005 207) - Uchaf addition (3rd reclassification)

Survey post for Craig Gwaun Taf

Significant Height Revisions post for Craig Gwaun Taf


There has been a new addition to the listing of Yr Uchafion instigated from a survey conducted with the Trimble GeoXH 6000.  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 of 15m of drop, the list is a joint compilation with Aled Williams.  Details relating to this list were published on the Mapping Mountains site in November 2015.

The hill is situated in the Bannau Brycheiniog group of hills in the heartland of the Brecon Beacons National Park in the northern part of south Wales and is situated southward of Corn Du and south-westward of Pen y Fan, with the latter hill being its Cardinal Hill, and is positioned above the towns of Aberhonddu (Brecon) to its north north-east and Merthyr Tudful (Merthyr Tydfil) to its south south-east.  The hill group of Bannau Brycheiniog are referred to in English as the Brecon Beacons and are positioned between the hills of Mynydd Epynt to their north and the hills of the south Wales valleys to their south.

The hill can be easily accessed from the car park at Pont ar Daf to its south south-west with the path leading toward the bwlch just north of its summit; Bwlch Duwynt, being on the Beacons Way and one of the main paths leading to the summit of south Wales’ highest mountain; Pen y Fan.  The hill can also be ascended from near to the Lower Neuadd Reservoir to its south-east where a path heads west to gain height on to the hill’s southerly ridge; this can then be followed to its summit.

The name of the hill is Craig Gwaun Taf and the survey conducted with the Trimble GeoXH 6000 was instigated through communication with Joe Nuttall, who had analysed the height of this hill’s summit and bwlch with LIDAR data.  LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales, and Joe has been diligently checking a number of hills for qualification to his parents 2,000ft list.  These lists are based on a minimum qualifying drop value of 15m and Joe found that LIDAR data gave Craig Gwaun Taf a drop of 15.783m.

However, as mentioned in the first paragraph of this post; if Craig Gwaun Taf has a minimum of 15m of drop it would also be included in the listing of Welsh hills at or over 500m in height that has a minimum of 15m of drop, and has the working title of Yr Uchafion.

Craig Gwaun Taf is given an 824m summit spot height on current Ordnance Survey maps that derives from the 2,704ft height on the series of old Six-Inch maps and has current bwlch contouring between 800m – 810m, with an 815m spot height on the area of the bwlch on the Ordnance Survey enlarged mapping on the Geograph website.  These figures give this hill an approximate c 13m of drop based on interpolation of bwlch contours, or only 9m of drop if based on the 815m Geograph spot height.  However, when Joe Nuttall analysed this hill with LIDAR data he found that it gave the summit as 825.885m and the bwlch as 810.102m, giving a drop value of 15.783m, sufficient for both Uchaf and Nuttall qualification.

The summit consists of a grassy hummock a few metres to the east of the ridge path that crosses the hill, and the 826.4m (converted to OSGM15) height produced by the Trimble is an average of three summit data sets.  On the day of the Trimble survey the bwlch consisted of an elongated shallow puddle stretching across the valley to valley traverse, and the 810.3m (converted to OSGM15) height produced by the Trimble is an average of two bwlch data sets taken from the same position, with a further two data sets also taken on the area of the bwlch, with one data set taken at either end of the shallow puddle.

This now revises the total in Yr Uchafion which will be updated accordingly and the hill is now listed as an Uchaf.


The full details for the hill are:

Cardinal Hill:  Pen y Fan

Summit Height:  826.4 (converted to OSGM15)

Name:  Craig Gwaun Taf

OS 1:50,000 map:  160

Summit Grid Reference:  SO 00548 20720 
   
Drop:  16.1m (converted to OSGM15)



The reclassifications to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains are as follows:


UCHAF ADDITIONS



UCHAF RECLASSIFICATIONS






Craig Gwaun Taf (SO 005 207, the extended ridge on the right) the new Uchaf



Myrddyn Phillips and Aled Williams (November 2016)







Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Graig Fach (SN 821 931) - Uchaf reclassified to 500m Sub-Uchaf (2nd reclassification)

Survey post for Graig Fach


There has been a reclassification of an Uchaf to a 500m Sub-Uchaf due to a survey conducted with the Trimble GeoXH 6000.  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 of 15m of drop, the list is a joint compilation with Aled Williams.  Details relating to this list were published on the Mapping Mountains site in November 2015.

The hill is situated in the Pumlumon group of hills in the heartland of northern mid Wales and is positioned to the south of Foel Fadian, which is the hill’s Cardinal Hill, and between the towns of Llanidloes to its south-east and Machynlleth to its north-west.  It can be easily accessed from a minor road to its north from where a track leads toward the lake of Glaslyn; the hill is positioned just to the west of this track.  Alternatively an extended route can be devised from its south where a path can be followed above the course of the Afon Hengwm.

The name of the hill is Graig Fach (the) little rock and was surveyed on 5th May 2016 in beautiful early morning sunshine.  Graig Fach has a 514m summit spot height and bwlch contouring between 490m – 500m with a 499m spot height appearing on the Ordnance Survey enlarged mapping on the Geograph website, this latter spot height is positioned on the track and interpolation suggests that it is not positioned where the critical bwlch is situated.

The bwlch consists of moor grass and heather and two data sets were taken, both within a few metres of one another, whilst the summit consists of moor grass and again, two data sets were taken resulting in the hill only having 14.5m of drop and therefore below the 15m minimum drop value required to qualify for the list.

This now revises the total of Uchaf hills which will be updated accordingly and the hill is now listed as a 500m Sub-Uchaf.


The full details for the hill are:

Cardinal Hill:  Foel Fadian

Summit Height:  513.1m (converted to OSGM15)

Name:  Graig Fach

OS 1:50,000 map:  135, 136

Summit Grid Reference:  SN 821 931

Drop:  14.5m (converted to OSGM15)



The reclassifications to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains are as follows:


RECLASSIFIED FROM UCHAF TO SUB-UCHAF





Graig Fach (SN 821 931) now reclassified from an Uchaf to a 500m Sub-Uchaf


Myrddyn Phillips and Aled Williams (May 2016)







Mapping Mountains - Hill Reclassifications - The Welsh 500m P15s (Yr Uchafion)

Pt. 649.8m (SH 660 452) - Uchaf reclassified to 500m Sub-Uchaf (1st reclassification) 

Survey post for Pt. 649.8m 


There has been a reclassification of an Uchaf to a 500m Sub-Uchaf due to a survey conducted by G&J Surveys.  Yr Uchafion is the informal title for the ‘Welsh 500m P15s’, a list jointly compiled with Aled Williams that takes in all hills in Wales at or above 500m that have a minimum of 15m of drop.  Details relating to this list are due to be published on the Mapping Mountains site in the near future.

The hill is situated in the Moelwynion and is positioned to the north of Moelwyn Mawr; which is its Cardinal Hill.  It can be easily accessed from the small communities of Croesor and Tanygrisiau; which are to the west and east respectively.

The hill is unnamed on Ordnance Survey maps, and therefore we are currently adopting the point / pwynt (Pt.) notation for it; this neutral protocol uses the summit height and therefore we have listed the hill as Pt. 649.8m.  However, this is only temporary as a locally known name is known by the authors, which will be used when the list receives full publication.

Pt. 649.8m was previously listed as having 15m of drop based on a series of Basic Levelling Surveys (BLS) conducted by Myrddyn Phillips in 1998, with the results sent to John and Anne Nuttall for their 2,000ft Welsh list of mountains.  When accepted into the Nuttalls list John and Anne coined the name Moelwyn Mawr North Ridge Top for this hill.  However,  its marginal status meant that it was always a prime candidate for being accurately surveyed, and this was subsequently done using two methods:  a line survey; the more accurate technique giving a drop of 14.8m, and GPS-based surveys, with the Leica GS15 also giving a drop of 14.8m and the Trimble GeoXH 6000 giving 14.9m.

This now revises the total of Uchaf hills which will be detailed in a future blog post, with the hill now listed as a 500m Sub-Uchaf.


The full details for the hill are:


Cardinal Hill:  Moelwyn Mawr

Summit Height:  649.8m (converted to OSGM15)

Name:  Pt. 649.8m

OS 1:50,000 map:  115

Summit Grid Reference:  SH 660 452

Drop:  14.8m


Pt. 649.8m on the right of photo with Moelwyn Mawr on the left towering over it

For details on the survey that reclassified this hill to 500m Sub-Uchaf status please click {here}


Myrddyn Phillips and Aled Williams (June 2015)

No comments: