Mapping Mountains – Hill Reclassifications – The Fours – The 400m Hills of England

Crook (SD 664 935) – 400m Sub-Four addition

There has been an addition to the listing of the The Fours – The 400m Hills of England, with the summit height, col height and their locations, the drop and status of the hill derived by Joe Nuttall who produced a summit analysis programme using LIDAR, and then by LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Crook (SD 664 935)

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

The Fours – The 400m Hills of England.  English hills at or above 400m and below 500m in height that have 30m minimum drop, accompanying the main listing of The Fours are three categories of sub hills, with this hill being added to the 400m Sub-Four category, the criteria for which are all English hills at or above 400m and below 500m in height that have 20m or more and below 30m of drop.  The list is co-authored by Myrddyn Phillips and Aled Williams and the 2^nd edition of the booklet containing this list was published by Mapping Mountains Publications on the 24^th April 2018.

The Fours - The 400m Hills of England by Myrddyn Phillips and Aled Williams

The name the hill is listed by is Crook, and it is adjoined to the The Calf group of hills, which are situated in the Howgill Fells (Region 35, Section 35A: The Northern Pennines), and it is positioned with the B6257 road to its west, the A684 road to its south and the A683 road to its east, and has the town of Sedbergh towards the south south-west.

When the 2^nd edition of the The Fours – The 400m Hills of England was published by Mapping Mountains Publications in April 2018, this hill was not included in the accompanying sub list, as it was considered not to meet the criteria used for this sub category. 

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

However, during the updating of this list for the 2^nd edition this hill was noted and listed with an estimated c 17m of drop, based on the 462m summit spot height that appears on the Harvey 1:25,000 Superwalker map to the Howgill Fells and an estimated c 445m col height based on interpolation of 10m contouring between 440m – 450m that appear on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Harvey 1:25,000 Superwalker map to the Howgill Fells

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 400m Sub-Four status is due to LIDAR analysis, resulting in a 464.7m summit height and a 444.4m col height, with these values giving this hill 20.3m of drop, which is sufficient for it to be classified as a 400m Sub-Four.

 

The full details for the hill are:

Group:  The Calf

Name:  Crook

OS 1:50,000 map:  98

Summit Height:  464.7m (LIDAR)

Summit Grid Reference:  SD 66458 93550 (LIDAR)

Col Height:  444.4m (LIDAR)

Col Grid Reference:  SD 66410 93726 (LIDAR)

Drop:  20.3m (LIDAR)

 

Our thanks to Ronnie Bowron for bringing the details of this hill to our attention.

For the additions, deletions and reclassifications to The Fours – The 400m Hills of England reported on Mapping Mountains since the December 2013 publication of the 1^st edition of this list by Europeaklist please consult the following Change Registers:

 

The Fours

 

The Fours – 400m Sub-Four

 

The Fours – 390m Sub-Four

 

The Fours – 390m Double Sub-Four

 

Myrddyn Phillips and Aled Williams (August 2022)

  

Mapping Mountains – Hill Reclassifications – The Welsh P15s

Moel y Crio (SJ 199 696) – Welsh Sub-P15 reclassified to Welsh P15

There has been a reclassification to the list of The Welsh P15s, with the summit height, bwlch height and their locations, the drop and status of the hill derived from a Trimble GeoXH 6000 survey conducted by Myrddyn Phillips with assistance from Mark Trengove.

 

Moel y Crio (SJ 199 696)

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

The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop.  The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10^th May 2019. 

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Moel y Crio, and it is adjoined to the Moel y Gamelin group of hills, which are situated in the north-eastern part of North Wales (Region A, Sub-Region A2), and it is positioned encircled by minor roads with the B5123 road farther to its east, and has the town of Yr Wyddgrug (Mold) towards the south-east.

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the P14 sub list with an estimated c 14m of drop, based on the 292m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 278m bwlch height, based on interpolation of 5m contouring between 275m – 280m that appear on the Ordnance Survey 1:25,000 Explorer map.

 

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

However, it was not until this hill was surveyed with the Trimble GeoXH 6000 that an accurate height for both its summit and connecting bwlch, and hence its drop could be ascertained.

 

The Trimble GeoXH 6000 gathering data at the summit of Moel y Crio

The Trimble GeoXH 6000 gathering data at the bwlch of Moel y Crio

Therefore, the reclassification of this hill from Welsh Sub-P15 status is due to a Trimble GeoXH 6000 survey, resulting in a 297.5m summit height and a 276.8m bwlch height, with these values giving this hill 20.7m of drop, which is sufficient for it to be included in the main list of The Welsh P15s. 

 

The full details for the hill are: 

Group:  Moel y Gamelin 

Name:  Moel y Crio 

OS 1:50,000 map:  116

Summit Height:  297.5m (converted to OSGM15) 

Summit Grid Reference:  SJ 19988 69614 

Bwlch Height:  276.8m (converted to OSGM15) 

Bwlch Grid Reference:  SJ 20406 69385 

Drop:  20.7m 

 

Myrddyn Phillips (August 2022)

 

 

 

 

 

  

Mapping Mountains – Significant Name Changes – 100m Twmpau and Y Trechol – The Dominant Hills of Wales

Field near Llan-gain Church (SN 382 155) 

There has been a Significant Name Change to a hill that is listed in the 100m Twmpau 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 LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Field near Llan-gain Church (SN 382 155)

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

100m Twmpau – Welsh hills at or above 100m and below 200m in height that have 30m minimum drop, with an accompanying sub list entitled the 100m Sub-Twmpau, with the criteria for this sub category being all Welsh hills at or above 100m and below 200m 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 100m Twmpau 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 Mynydd Pencarreg group of hills, which are situated in the south-western part of South Wales (Region B, Sub-Region B1), and it is positioned with the B4312 road to its north-west and a minor road to its south-east, and has the town of Caerfyrddin (Carmarthen) towards the north-east.

The hill appeared in the original Welsh 100m P30 list on Geoff Crowder’s v-g.me website, under the invented and transposed name of Bryn Llangain, with an accompanying note stating; Name from town to the North.

 

Bryn Llangain

110c

SN382156

159

177/178

Name from town to the North.

During my early hill listing I thought it appropriate to either invent a name for a hill, or use a name that appeared near to the summit of the hill on Ordnance Survey maps of the day.  My preference was to use farm names and put Pen, Bryn or Moel in front of them or as in this instance transpose the name of a village and add the word Bryn to it.  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, through this form of research an appropriate name for the hill can usually be found. 

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

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

Extract from the Tithe map

The enclosed land where the summit of this hill is situated is given the number 19 on the Tithe map, this can be cross referenced against the apportionments; it is these apportionments that give the name of the owner or occupier of the land as well as the name of the land.  The land where the summit of this hill is situated is named as Field near Llan-gain Church in the apportionments, with the details on the Tithe map appearing in the parish of Llan-gain and in the county named as Carmarthen. 

Extract from the apportionments

Therefore, the name this hill is now listed by in the 100m Twmpau and Y Trechol – The Dominant Hills of Wales is Field near Llan-gain Church, and this was derived from the Tithe map. 

 

The full details for the hill are:

Group:  Mynydd Pencarreg

Name:  Field near Llan-gain Church

Previously Listed Name:  Bryn Llangain   

OS 1:50,000 map:  159

Summit Height:  111.0m (LIDAR) 

Summit Grid Reference:  SN 38227 15593 (LIDAR) 

Bwlch Height:  68.6m (LIDAR) 

Bwlch Grid Reference:  SN 37428 17929 (LIDAR) 

Drop:  42.4m (LIDAR) 

Dominance:  38.20% (LIDAR) 

 

Myrddyn Phillips (August 2022)

  

Mapping Mountains – Hill Reclassifications – Y Trichant – The 300m Hills of Wales

Lower Field (SJ 137 155) – Trichant reclassified to Sub-Trichant

There has been confirmation of a reclassification to the list of 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 a Trimble GeoXH 6000 survey conducted by Myrddyn Phillips with assistance from Mark Trengove. 

LIDAR image of Lower Field (SJ 137 155)

The criteria for the list that this reclassification 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 name the hill is now listed by is Lower Field and this was derived from the Tithe map, and it is adjoined to the Foel Cedig group of hills, which are situated in the southern part of North Wales (Region A, Sub-Region A3), and it is positioned encircled by minor roads, with the A490 road farther to its north-east, the B4393 road farther to its north-west, the B4382 road farther to its west and the A495 road farther to its south-east, and has the village of Meifod towards the south-east.

When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was included as the prioritised summit in the main P30 list with an accompanying note stating; Two points of same height (Gallt y Goedhwch SJ137159), with Gallt y Goedhwch listed as the qualifying P20. 

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

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 24m of drop, based on an estimated c 320m summit height and an estimated c 296m bwlch height, with both heights based on interpolation of 10m contouring that appears on the Ordnance Survey 1:25,000 Explorer map, with the prioritised summit given to Gallt y Goedhwch.

However, it was not until the survey with the Trimble GeoXH 6000 that the details for this hill could be accurately re-assessed.  The hill has also now been analysed by LIDAR (Light Detection & Ranging); a technique which produced highly accurate height data that is now freely available for much of England and Wales. 

The Trimble GeoXH 6000 gathering data at the summit of Lower Field

The Trimble GeoXH 6000 gathering data at the bwlch of Lower Field

Therefore, the confirmation of the reclassification of this hill from Trichant status is due to a Trimble GeoXH 6000 survey, resulting in a 321.1m summit height and a 295.3m bwlch height, with these values giving this hill 25.8m of drop, which is sufficient for it to be classified as a Sub-Trichant. 

 

The full details for the hill are: 

Group:  Foel Cedig 

Name:  Lower Field 

OS 1:50,000 map:  125

Summit Height:  321.1m (converted to OSGM15)                                                           

Summit Grid Reference:  SJ 13704 15586                                     

Bwlch Height:  295.3m (converted to OSGM15) 

Bwlch Grid Reference:  SJ 13681 15650 

Drop:  25.8m 

 

Myrddyn Phillips (August 2022)

 

 

 

 

  

Mapping Mountains – Trimble Surveys – Banc Llechwedd Mawr

 

09.07.22  Disgwylfa Fawr (SN 737 847) and Disgwylfa Fach (SN 736 838) 

Disgwylfa Fawr (SN 737 847)

As the forecast gave for particularly warm conditions from late morning on, we had a relatively early start having driven down the track leading to Llyn Syfydrin.  This lake is positioned in the heartland of the Pumlumon range and gives easy access to Disgwylfa Fawr and its adjacent hills.  We planned on visiting two hills on this first walk of the day.  However, there are a number of P30s in this area, many of which can be combined during extended walks via connecting tracks through quiet, almost forgotten land. 

Llyn Syfydrin

Intermittent cloud gave some respite from the sun as we left the car and made our way on the track leading toward the old building of Syfydrin.  Before reaching this we branched leftward on another track; unmarked on my map, which steadily gained height before levelling off.  This approach headed direct toward the western flank of Disgylfa Fawr, a hill I had only visited once before in March 2003, when along with Eryl and Stephen we visited six hills during a 5 hour 15 minute walk starting from the western shore of the Dinas Reservoir.  On this first visit this land left me with an impression of openness and wildness, with bleached moor and remains of old farm houses adding a feeling of abandoned tranquillity. 

Aled heading up the steep slopes of Disgwylfa Fawr

Nowadays earthen tracks indicating the off road use of trail bikes gauge part of this land and two of these tracks led steeply up the western flank of Disgwylfa Fawr.  I put my head down and ever so slowly started on the steep uphill plod, whilst Aled wisely took a route contouring up and waited for me at the top of the steep section.  Occasionally I rested, turned and looked down toward the lake and the continuation of land as it headed westward toward the sea, which this morning crested the horizon, temptingly blue with its straight lined edge piecing the point between sea and sky. 

Taking a rest whilst on the steep section

Once over the steepest section I followed Aled as he headed toward the summit of the hill, which is crowned with a small cairn.  The views from this vantage point are extensive and whilst I set the Trimble up to gather data, Aled sat looking north out toward the expanse of Nant y Moch Reservoir and a multitude of hills that radiated out in all directions. 

LIDAR summit image of Disgwylfa Fawr

Prior to visiting these hills Aled had analysed them via available LIDAR which only covers the higher of the two.  With the summit now being Trimbled the LIDAR would at least give an accurate height and position for the bwlch of Disgwylfa Fawr. 

LIDAR bwlch image of Disgwylfa Fawr

As the Trimble slowly beeped away gathering its individual datum points, I sat beside Aled whilst a slight breeze blew across the upper hill.  When data are collected gives time for my body to rest, with my mind taking over with conversation and view to enjoy.  All too soon though, the Trimble had gathered its allotted data and once switched off and photographs taken we headed down the southern slopes toward our second hill of the day; Disgwylfa Fach. 

The inward route from Llyn Syfydrin

Aled at the summit of Disgwylfa Fawr

Gathering data at the summit of Disgwylfa Fawr

Between Disgwylfa Fawr and Disgwylfa Fach is the critical bwlch for the latter, smaller heighted hill.  A fence followed the course of the bwlch in the valley to valley direction.  Either side of the fence was a mass of high reed grass, indicating bog.  We had encountered slithers of peaty wetness on the lower part of our walk down to this bwlch and even though it was high summer the ground was still wet.  In winter this would probably be a quagmire.  We debated where the critical point of the bwlch was positioned and decided it roughly followed the course of the fence and therefore I placed the Trimble on a convenient fence post, took a measurement offset between its internal antenna and the ground at its base and as Aled made his way through almost waist high reed grass to the relative comfort of the grassland beyond, I set the equipment to gather data. 

Heading toward Disgwylfa Fach

Crossing the bwlch

As the Trimble gathered its allotted data I initially lay on the reed grass below the equipment, but my shorts soon got wet and therefore I spent five minutes or so kneeling on tussocks of reed grass endeavouring to remain as dry as I could. 

My view during the bwlch survey

Gathering data at the bwlch of Disgwylfa Fach

It proved a slow plod up to the summit of Disgwylfa Fach.  At this time of year great swathes of the Pumlumon hills are covered in thick grassland, which can be torturous to walk through.  The route from bwlch to summit was not great in distance but was pathless, first through the reed grass at the bwlch followed by thick grass on the upper slopes.  It was heavy going and especially as the sun was increasing in strength and the temperature was ebbing ever upward. 

Gathering data at the summit of Disgwylfa Fach

As the Trimble gathered data from the summit of Disgwylfa Fach I again joined Aled and sat, relaxed and enjoyed the view.  Moments like this are to be savoured as all too soon the five minutes usually allocated for data collection are over and it is time to pack the equipment away and head off. 

The grasslands of the Pumlumon hills

We now had to reclaim lost height to crest the broad south-western ridge of Disgwylfa Fawr.  This was relatively easy with sheep paths followed leading us back to our inward track above the old building of Syfydrin.  By the time we arrived back at the car the temperature had rocketed.  But there were still two more walks to do, both relatively small in length, with just one for me whilst Aled planned on doing the both. 

Almost back at the car

Leaving Llyn Syfydrin I drove up the track to the narrow paved road and followed this southward toward Ponterwyd and then connected with another narrow road heading north toward Nant y Moch Reservoir, which in time led us toward our next track leading toward Banc yr Ŵyn (SN 741 902); which for me would be my last hill of a very hot day. 

 

Survey Result 

 

Disgwylfa Fawr

Summit Height:  506.1m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SN 73729 84737 (Trimble GeoXH 6000)

Bwlch Height:  352.5m (LIDAR)

Bwlch Grid Reference:  SN 73605 86685 (LIDAR)

Drop:  153.6m (Trimble GeoXH 6000 summit and LIDAR bwlch)

Dominance:  30.35% (Trimble GeoXH 6000 summit and LIDAR bwlch)

 

 

Disgwylfa Fach

Summit Height:  414.2m (converted to OSGM15)

Summit Grid Reference:  SN 73653 83882

Bwlch Height:  375.4m (converted to OSGM15)

Bwlch Grid Reference:  SN 73652 84116

Drop:  38.8m

Dominance:  9.36%

 

 

For further details please consult the Trimble Survey Spreadsheet