Mapping Mountains – Hill Reclassifications – Y Trechol – The Dominant Hills of Wales

 

Pen Lan Fawr (SN 626 222) – Lesser Dominant addition

There has been an addition to the listing of Y Trechol – The Dominant Hills of Wales, with the summit height, bwlch height and their locations, the drop, dominance and status of the hill confirmed by LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Pen Lan Fawr (SN 626 222)

The criteria for the list that this addition applies to are:

Y Trechol – The Dominant Hills of Wales – Welsh P30 hills whose prominence equal or exceed half that of their absolute height.  With the criteria for Lesser Dominant status being those additional Welsh P30 hills whose prominence is between one third and half that of their absolute height.  The list is authored by Myrddyn Phillips with the Introduction to the start of the Mapping Mountains publication of this list appearing on the 3^rd December 2015, and the list is now available in its entirety on Mapping Mountains in Google Doc format. 

Y Trechol - The Dominant Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Pen Lan Fawr and it is adjoined to the Mynydd Mallaen group of hills, which are situated in the central part of South Wales (Region B, Sub-Region B1), and it is positioned with a minor road to its north, the Afon Tywi to its south and the A483 road to its east, and has the town of Llandeilo towards the north-east.

When the original 30-99m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was included in the accompanying Hills to be surveyed sub list, as it was considered not to meet the criteria then used in the main P30 category.

When the sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-evaluated and it was listed with an estimated c 29m of drop, based on the 95m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 66m bwlch height, based on interpolation of 10m contouring between 60m – 70m. 

Extract from the Ordnance Survey 1:25,000 Explorer map

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current and digitally updated such as the interactive mapping on the Magic Maps and WalkLakes websites.

The details for this hill were re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map became available online.  This mapping had many spot heights not on other publicly available Ordnance Survey maps and for this hill it had a 65m bwlch spot height, and when coupled with the 95m summit spot height these values gave this hill 30m of drop, with this drop value not giving the hill sufficient dominance to be included as a Lesser Dominant hill.

However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.

Therefore, the addition of this hill to Lesser Dominant status is due to LIDAR analysis, resulting in a 98.3m summit height and a 64.9m bwlch height, with these values giving this hill 33.4m of drop and 33.97% dominance, which is sufficient for it to be classified as a Lesser Dominant hill. 

 

The full details for the hill are:

Group:  Mynydd Mallaen

Name:  Pen Lan Fawr

OS 1:50,000 map:  159

Summit Grid Reference:  SN 62626 22229 (LIDAR)

Summit Height:  98.3m (LIDAR)

Bwlch Grid Reference:  SN 61761 22561 (LIDAR)

Drop Summit to Bwlch:  33.4m (LIDAR)

Drop Bwlch to ODN:  64.9m (LIDAR)

Dominance:  33.97% (LIDAR)

 

Myrddyn Phillips (April 2022)

 

 

 

 

 

Mapping Mountains – Significant Name Changes – Y Trichant – The 300m Hills of Wales and Y Trechol – The Dominant Hills of Wales

Yr Aran (SJ 174 260) 

There has been a Significant Name Change to a hill that is listed in the Y Trichant – The 300m Hills of Wales and Y Trechol – The Dominant Hills of Wales, with the summit height, bwlch height and their locations, the drop, dominance and status of the hill derived from detail on contemporary maps produced from Ordnance Survey data. 

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

Y Trichant – The 300m Hills of Wales – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant, with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.  The list is authored by Myrddyn Phillips with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13^th May 2017, and the Introduction to the Mapping Mountains publication of the list appearing on the 1^st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

Y Trechol – The Dominant Hills of Wales – Welsh P30 hills whose prominence equal or exceed half that of their absolute height.  With the criteria for Lesser Dominant status being those additional Welsh P30 hills whose prominence is between one third and half that of their absolute height.  The list is authored by Myrddyn Phillips with the Introduction to the start of the Mapping Mountains publication of this list appearing on the 3^rd December 2015, and the list is now available in its entirety on Mapping Mountains in Google Doc format. 

Y Trechol - The Dominant Hills of Wales by Myrddyn Phillips

The hill is adjoined to the Craig Berwyn group of hills, which are situated in the eastern part of North Wales (Region A, Sub-Region A3), and it is positioned with the B4580 road to its north, minor roads to its west and east and the B4396 road to its south, and has the village of Llangedwyn towards the south-east.

The hill appeared in the original Welsh 300m P30 list on Geoff Crowder’s v-g.me website, under the name of Mynydd-y-briw; which is a prominent name that appears close to the summit of this hill on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map.

Mynydd-y-briw

341m

SJ174260

125

239

Marilyn. Clem/Yeaman.

 

During my early hill listing I paid little regard to name placement on the map, or the meaning of names and to what feature the name was appropriately applied to.  Therefore, I prioritised names for listing purposes that I now understand are either inappropriate or where another name is viewed as being more appropriate.  This is not a practice that I now advocate as with time and inclination place-name data can be improved either by asking local people or by examining historic documents. 

Extract from the Ordnance Survey 1:25,000 Explorer map

When compiling the Y Trechol – The Dominant Hills of Wales list I made place-name enquires regarding this hill with one of the local farmers; who was the father of a friend of an ex-girlfriend.  I was told by the local farmer that the hill is known as Yr Aran.

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current and digitally updated such as the interactive mapping on the Magic Maps and WalkLakes websites.  One of the historic maps now available online is the Ordnance Survey Draft Surveyors map which formed the basis for the first publicly available Ordnance Survey One-Inch ‘Old Series’ map, and it is the Draft Surveyors map along with the Ordnance Survey Six-Inch map that substantiates the information the local farmer gave me.

The Draft Surveyors maps consist of the preliminary drawings made by the Ordnance Survey surveyors between the 1780s and 1840 and formed the basis for the first publicly available One-Inch map.  They were drawn at scales of six inches to the mile for areas considered of particular military significance and down to two inches to the mile for other areas.  Fair copies were then produced from these preliminary drawings to one inch to the mile and then copper plates were prepared for printing.  The Draft Surveyors maps for the whole of Wales are now available online and they form an important part in the study of Welsh upland place-names as they bridge the time frame between the late 18^th century and the mid-19^th century when the Ordnance Survey produced their first One-Inch maps, and importantly for this hill and its listed name, it is this map that names the hill as Yr Aran. 

Extract from the Ordnance Survey Draft Surveyors map

The Ordnance Survey series of Six-Inch maps formed the base map Ordnance Survey used for many decades leading to the production of the 1:10,000 Series of maps, both have now been superseded by the digitised Master Map.  The series of Six-Inch maps are excellent for name placement and especially so compared to the contemporary Ordnance Survey 1:25,000 Explorer map, and it is the series of Six-Inch maps that name this hill as Aran, with the definite article Yr not given.  The detail given on the Ordnance Survey series of Six-Inch maps is also reproduced on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map. 

Extract from the Ordnance Survey series of Six-Inch maps

Therefore, the name this hill is now listed by in the Y Trichant – The 300m Hills of Wales and Y Trechol – The Dominant Hills of Wales is Yr Aran, and this was derived from local enquiry and substantiated by the Ordnance Survey Draft Surveyors map and the Ordnance Survey series of Six-Inch maps, with the caveat of the retention of the definite article Yr as given by local enquiry. 

 

The full details for the hill are: 

Group:  Craig Berwyn 

Name:  Yr Aran 

Previously Listed Name:  Mynydd-y-briw 

OS 1:50,000 map:  125

Summit Height:  341m (spot height)                                                           

Summit Grid Reference:  SJ 17404 26074 (hand-held GPS via DoBIH) 

Bwlch Height:  c 181m (interpolation) 

Bwlch Grid Reference:  SJ 17597 26834 (interpolation) 

Drop:  c 160m (spot height summit and interpolated bwlch) 

Dominance:  46.92% (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (April 2022)

 

 

  

Mapping Mountains – Trimble Surveys – Pumlumon

04.03.22  Pen Rallt (SN 951 859)

LIDAR image of Pen Rallt (SN 951 859)

I had visited this hill once before in January 2004 when it formed one of five walks during the day, then I approached from the minor road to its west and scampered up and down in 14 minutes.  Today was a more leisurely affair, it also proved much wetter!  Prior to visiting the hill I had conducted LIDAR analysis for its summit and connecting bwlch, and had come prepared with the necessary ten figure grid references for both.

On my previous visit I considered the pastured grass of a grazing field on the northern section of the upper ridge, to be slightly higher than an artificially raised green on the opposite side of the ridge fence and which makes up a part of Llanidloes Golf Club.  As there is a large parking area at the Golf Club I thought this would give easy access to the high point and as this was the third walk and fourth hill of the day it would also hopefully give me a leisurely saunter to its summit, before visiting friends in town followed by a dinner party later in the evening.

As I drove toward the Golf Club the heavens opened, I hoped this would be no more than a passing shower, but as I drew up and parked the rain battered my car for the next 45 minutes.  Peering out of the rain splattered window the sky to my north had taken on a slate grey and foreboding look.  It continued like this for quite some time.  All I wanted was a 30 minute gap to scamper up, survey the summit and plod back down, and ideally followed by a few minutes of dry weather to visit Penrallt; the local farm just below the Club House to make place- name enquiries about the hill and then a few more minutes without any rain to change and get dry and clean clothes on for my impending evening’s entertainment.

Slowly the downpour lessened and as what I then thought to be the last rain drops fell, I decided to go for it and gathered all necessary equipment, locked my car and started up a very soggy driving range toward the upper part of the golf course.  As I did so it started to rain again!

Reaching the high point of the golf course I looked out across the valley toward a greyed scene where Bryn y Fan was silhouetted in rain, it swept across the land.  Even though I had not got my wet proofs on I would usually have just bagged the high point and very quickly descended back to the car.  However, surveying requires a little more methodology!  I decided the best course of action was to wait out the rain and therefore I stood behind a hawthorn tree for 20 minutes or so with my back to the rain watching it sweeping across the land to my south.  Great drops of wet stuff fell on me from the tree, I tried shielding the Trimble which was already switched on and logged in to a number of satellites, whilst also shielding my camera which was dangling around my neck.  I should have been more patient and remained in my car for another 30 minutes until the grey rain cloud had definitely passed.  But here I was, getting soggy and cold standing behind a hawthorn tree.  I related this story to a friend later in the evening; they replied that it was a wonder I wasn’t arrested, which brought a smile to face.

The rain eventually stopped and brought glimmers of sunshine, with the late afternoon colour to be savoured after such wet conditions which consisted of silvered grey dullness.  I quickly left the confines of my hawthorn tree as the last few drops of rain skirted the upper part of the hill. 

Bryn y Fan

The high point of the golf course was just behind me and I was soon on top of it looking out toward the high point of the grazing field on the opposite side of the intervening barb wired fence.  This part of the golf course was artificially raised and my eye agreed with what LIDAR also gives; that the natural ground in the grazing field is higher.  I was soon over the fence taking photographs as the low light gave wonderful colour.

Soon the Trimble was placed on what I judged the highest part of this hill and as it quietly beeped away collecting its individual datum points I looked out toward Bryn y Fan, which was now bathed in delicate colour. 

Gathering data at the summit of Pen Rallt

Once the allotted five minutes of summit data were gathered and stored, I closed the equipment down, packed it away and sauntered back over the fence and wandered down the golf course to my awaiting car.  I now wanted to call at the farm which is just below the Club House.

I met Janet Breeze at the farm, her husband; Graham was out lambing.  Janet told me that the whole hill including the golf course and the high grazing field where I had just gathered data from was a part of Pen Rallt land and it is known by that name. 

Janet Breeze of Penrallt farm

I thanked Janet for her time and drove the short distance down the access road to the Golf Club and back in to Llanidloes to find a quiet spot to change before visiting Eryl and Rita, followed by another excellent dinner party with much merriment and raucous laughter at Suzanne’s.  I was home by just before midnight; it had proved a wonderful day with three walks and four hills visited, with one marginal hill confirmed as a P30, local farmers met, names of hills confirmed, friends visited and excellent food, conversation and company had. 

 

Survey Result: 

 

Pen Rallt (significant name change)

Summit Height:  301.9m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SN 95168 85960 (Trimble GeoXH 6000)

Bwlch Height:  223.9m (LIDAR)

Bwlch Grid Reference:  SN 94689 85959 (LIDAR)

Drop:  78.0m (Trimble GeoXH 6000 summit and LIDAR bwlch)

Dominance:  25.84% (Trimble GeoXH 6000 summit and LIDAR bwlch)

 

 

For further details please consult the Trimble Survey Spreadsheet

 

  

Mapping Mountains – Hill Reclassifications – 30-99m Twmpau

Pen Lan Fawr (SN 626 222) – 30-99m Sub-Twmpau reclassified to 30-99m Twmpau 

There has been confirmation of a reclassification to the list of 30-99m Twmpau, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Pen Lan Fawr (SN 626 222)

The criteria for the list that this reclassification applies to are:

30-99m Twmpau – Welsh hills at or above 30m and below 100m in height that have 30m minimum drop, with an accompanying sub list entitled the 30-99m Sub-Twmpau, with the criteria for this sub category being all Welsh hills at or above 30m and below 100m in height with 20m or more and below 30m of drop, with the word Twmpau being an acronym standing for thirty welsh metre prominences and upward. 

The 30-99m Twmpau by Myrddyn Phillips

The name the hill is listed by is Pen Lan Fawr and it is adjoined to the Mynydd Mallaen group of hills, which are situated in the central part of South Wales (Region B, Sub-Region B1), and it is positioned with a minor road to its north, the Afon Tywi to its south and the A483 road to its east, and has the town of Llandeilo towards the north-east.

When the original 30-99m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was included in the Hills to be surveyed sub list, as it was considered not to meet the criteria then used for the P30 category.

When the sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-evaluated and it was listed with an estimated c 29m of drop, based on the 95m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 66m bwlch height, based on interpolation of 10m contouring between 60m – 70m. 

Extract from the Ordnance Survey 1:25,000 Explorer map

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current and digitally updated such as the interactive mapping on the Magic Maps and WalkLakes websites.

The details for this hill were re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map became available online.  This mapping had many spot heights not on other publicly available Ordnance Survey maps and for this hill it had a 65m bwlch spot height, and when coupled with the 95m summit spot height these values gave this hill 30m of drop.

However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.

Therefore, the confirmation of the reclassification of this hill from 30-99m Sub-Twmpau status is due to LIDAR analysis, resulting in a 98.3m summit height and a 64.9m bwlch height, with these values giving this hill 33.4m of drop, which is sufficient for it to be classified as a 30-99m Twmpau. 

 

The full details for the hill are: 

Group:  Mynydd Mallaen 

Name:  Pen Lan Fawr 

OS 1:50,000 map:  159

Summit Height:  98.3m (LIDAR) 

Summit Grid Reference:  SN 62626 22229 (LIDAR)               

Bwlch Height:  64.9m (LIDAR) 

Bwlch Grid Reference:  SN 61761 22561 (LIDAR) 

Drop:  33.4m (LIDAR) 

 

Myrddyn Phillips (April 2022)

 

 

 

  

Mapping Mountains – Significant Name Changes – Y Trichant – The 300m Hills of Wales

Y Foel (SJ 207 315) 

There has been a Significant Name Change to a hill that is listed in the Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Y Foel (SJ 207 315)

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

Y Trichant – The 300m Hills of Wales – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant, with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.  The list is authored by Myrddyn Phillips with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13^th May 2017, and the Introduction to the Mapping Mountains publication of the list appearing on the 1^st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The hill is adjoined to the Craig Berwyn group of hills, which are situated in the eastern part of North Wales (Region A, Sub-Region A3), and it is positioned encircled by minor roads, with the B4500 road farther to its north-west and the B4580 road farther to its south-east, and has the village of Glyn Ceiriog towards the north.

When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was not included in the Hills to be surveyed sub list, as it was considered not to meet the criteria then used for this sub category.

After the sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-assessed and it was listed under the point (Pt. 307m) notation with 26m of drop, based on the 307m summit spot height and the 281m bwlch spot height that appear on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current and digitally updated such as the interactive mapping on the Magic Maps and WalkLakes websites.  One of the historic maps now available online is the Ordnance Survey Draft Surveyors map which formed the basis for the first publicly available Ordnance Survey One-Inch ‘Old Series’ map, and it is the Draft Surveyors map that forms the basis for the change in the listed name of this hill. 

Extract from the Ordnance Survey Draft Surveyors map

The Draft Surveyors maps consist of the preliminary drawings made by the Ordnance Survey surveyors between the 1780s and 1840 and formed the basis for the first publicly available One-Inch map.  They were drawn at scales of six inches to the mile for areas considered of particular military significance and down to two inches to the mile for other areas.  Fair copies were then produced from these preliminary drawings to one inch to the mile and then copper plates were prepared for printing.  The Draft Surveyors maps for the whole of Wales are now available online and they form an important part in the study of Welsh upland place-names as they bridge the time frame between the late 18^th century and the mid-19^th century when the Ordnance Survey produced their first One-Inch maps, and importantly for this hill and its listed name, it is this map that names the hill as Y Foel.

Therefore, the name this hill is now listed by in the Trichant – The 300m Hills of Wales is Y Foel, and this was derived from the Ordnance Survey Draft Surveyors map. 

 

The full details for the hill are: 

Group:  Craig Berwyn 

Name:  Y Foel 

Previously Listed Name:  Pt. 307m 

OS 1:50,000 map:  126

Summit Height:  307.3m (LIDAR)                                                           

Summit Grid Reference:  SJ 20741 31551 (LIDAR) 

Bwlch Height:  280.7m (LIDAR) 

Bwlch Grid Reference:  SJ 20979 31667 (LIDAR) 

Drop:  26.6m (LIDAR) 

 

Myrddyn Phillips (April 2022)