Y
Pellennig –The Remotest Hills of Wales – Hill Reclassifications
Y Pellennig –The Remotest Hills of Wales are all Welsh hills whose
summit is 2.5km or more from the nearest paved public road and have a minimum drop
of 15m, with the Change Register to this list available on Mapping Mountains.
The list is co-authored by Myrddyn
Phillips and Aled Williams and the posts that have appeared on Mapping
Mountains detailing the additions and deletions to this list appear below
presented chronologically in receding order.
Mapping Mountains - Hill Reclassifications - Y Pellennig - The Remotest Hills of Wales
Pt. 526.8m (SN 745 611) – Pellennig deletion(12th reclassification)
There has been a deletion to the listing of Y Pellennig – The Remotest 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 summit survey and LIDAR bwlch analysis conducted by Myrddyn Phillips and Aled Williams.
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| Pt. 526.8m (SN 745 611) |
The criteria for the list that this deletion applies to are:
Y Pellennig – The Remotest Hills of Wales - Welsh hills whose summit is at least 2.5km from the nearest paved public road and the hill has 15m minimum drop. The list is co-authored by Myrddyn Phillips and Aled Williams and is available as a downloadable e-booklet and print-booklet version on Mapping Mountains Publications with the up-to-date master list available to download on the Mapping Mountains site in Google Doc format.
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| Y Pellennig - The Remotest Hills of Wales by Myrddyn Phillips and Aled Williams |
The hill is being listed by the point (Pt. 526.8m) notation and it is adjoined to the Esgair Wen 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 and south, and has the small community of Pontrhydfendigaid towards the north-west and the town of Tregaron towards the west.
When the original list that later became known as the Y Pellennig – The Remotest Hills of Wales was first compiled, this hill was not included as with a 527m summit spot height and bwlch contouring between 510m – 520m that appear on the contemporary Ordnance Survey 1:25,000 Explorer map, interpolation gave this hill less than 15m of drop.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Since the original compilation of this list 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 resources recently available online is the mapping on the OS Maps website and the details for this hill were subsequently re-assessed against this mapping. This is the replacement for OS Get-a-map and until recent times had contours at 5m intervals which were proving consistently more accurate compared to the 5m contours that sometimes appear on the Ordnance Survey 1:25,000 Explorer map and used to appear on the online Vector Map Local. This mapping had bwlch contouring between 510m – 515m, with interpolation placing the height of the bwlch as an estimated c 511m, and when coupled with the 527m summit spot height these values gave this hill an estimated c 16m of drop, and therefore it was included as a Pellennig with 2.700km of remoteness.
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| Extract from the interactive mapping that was hosted on the OS Maps website |
The hill was subsequently surveyed with the Trimble GeoXH 6000, resulting in a 526.8m summit height and a 511.9m bwlch height. Although this survey gave this hill 14.9m of drop, it was decided that the bwlch position was incorrect and therefore the hill was retained as a Pellennig.
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| The Trimble GeoXH 6000 gathering data at the summit of Pt. 526.8m (SN 745 611) |
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.
%20-%20LIDAR%20hill%202.jpg) |
| LIDAR image of Pt. 526.8m (SN 745 611) |
Therefore, the deletion of this hill from Pellenig status is due to a Trimble GeoXH 6000 summit survey and LIDAR bwlch analysis, resulting in a 526.8m summit height and a 512.0m bwlch height, with these values giving this hill 14.8m of drop, which is insufficient for it to be classified as a Pellennig.
The full details for the hill are:
Group: Esgair Wen
Name: Pt. 526.8m
OS 1:50,000 map: 146, 147
Summit Height: 526.8m (Trimble GeoXH 6000)
Summit Grid Reference: SN 74595 61119 (Trimble GeoXH 6000)
Bwlch Height: 512.0m (LIDAR)
Bwlch Grid Reference: SN 74980 61422 (LIDAR)
Drop: 14.8m (Trimble GeoXH 6000 summit and LIDAR bwlch)
Remoteness: 2.700km (no longer applicable)
For the additions and deletions to Y Pellennig – The Remotest Hills of Wales reported on Mapping Mountains please consult the following Change Register:
Y Pellennig – The Remotest Hills of Wales
Aled Williams and Myrddyn Phillips (November 2023)
Mapping Mountains - Hill Reclassifications - Y Pellennig - The Remotest Hills of Wales
Twll y Gwyddel (SM 705 225) – Pellennig addition (11th reclassification)
Twll y Gwyddel (SM 705 225) – Pellennig addition (11th reclassification)
There has been an addition to the listing of Y Pellennig – The Remotest Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis conducted by Aled Williams.
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| Twll y Gwyddel (SM 705 225) |
The criteria for the list that this addition applies to are:
Y Pellennig – The Remotest Hills of Wales - Welsh hills whose summit is at least 2.5km from the nearest paved public road and the hill has a minimum 15m of drop, the list is a joint compilation between Myrddyn Phillips and Aled Williams and is available as a downloadable e-booklet or print-booklet version on Mapping Mountains Publications with the up-to-date master list available on the Mapping Mountains site in Google Doc format.
This hill is a stack and it is found in Twll y Gwyddel and is adjoined to the Carn Llidi group of hills which are situated in the south-western part of Mid and West Wales (Region B, Sub-Region B4), and it is positioned with the southern part of Ynys Dewi to its north and Ynys Cantwr to its south.
This hill was not included when the original list of Pellennig hills was compiled as contemporary Ordnance Survey 1:25,000 Explorer maps do not give it any contour ring. The lack of contour rings is also applicable to the Ordnance Survey Vector Map Local hosted on the Geograph website which is entitled the Interactive Coverage Map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
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| Extract from the Ordnance Survey Vector Map Local hosted on the Geograph website |
The details for this area were re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and has 5m contour intervals. But even this map does not show this hill as having any contour rings.
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| Extract from the OS Maps website |
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.
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| LIDAR DSM image of the stack found in Twll y Gwyddel. 1m contour (black), 10m contour (red) and sea level (yellow). |
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LIDAR DSM image of the stack found in Twll y Gwyddel. Black lines represent 1m contours, yellow lines represent sea level below which is coloured dark blue. Coloured shading represents land between 1m contours. Red line denotes the valley-to-valley traverse through the boulders which are found between the stack and Foel Fawr to the north
The addition of this hill to Pellennig status is due to LIDAR analysis, resulting in a 16.4m summit height and a 0.8m bwlch height, with these values giving this hill 15.6m of drop, and with the distance between its summit and the nearest paved public road being 3.300km, it gives this hill sufficient remoteness and drop for Pellennig status.
The full details for the hill are:
Group: Carn Llidi
Name: Twll y Gwyddel
OS 1:50,000 map: 157
Summit Height: 16.4m (LIDAR)
Summit Grid Reference: SM 70552 22500 (LIDAR)
Bwlch Height: 0.8m (LIDAR)
Bwlch Grid Reference: SM 70545 22512 (LIDAR)
Drop: 15.6m (LIDAR)
Remoteness: 3.300km
For the additions and deletions to Y Pellennig – The Remotest Hills of Wales reported on Mapping Mountains please consult the following Change Register:
Myrddyn Phillips and Aled Williams (July 2019)
© Crown: CHERISH PROJECT 2019. Produced with EU funds through the Ireland Wales Co-operation Programme 2014-2020. All material made freely available through the Open Government Licence.
Pt. 22.2m (SM 701 226) – Pellennig addition (10th reclassification)
Significant Height Revisions post for Pt. 22.2m
There has been an addition to the listing of Y Pellennig – The Remotest Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis conducted by Aled Williams.
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| Pt. 22.2m (SM 701 226) |
The criteria for the list that this addition applies to are:
Y Pellennig – The Remotest Hills of Wales - Welsh hills whose summit is at least 2.5km from the nearest paved public road and the hill has a minimum 15m of drop, the list is a joint compilation between Myrddyn Phillips and Aled Williams and is available as a downloadable e-bookletor print-booklet version on Mapping Mountains Publications with the up-to-date master list available on the Mapping Mountains site in Google Doc format.
As the authors do not know an appropriate name for this hill either from historic research or local enquiry it is being listed by the point (Pt. 22.2m) notation, and it is adjoined to the Carn Llidi group of hills which are situated in the south-western part of Mid and West Wales (Region B, Sub-Region B4), and it is positioned in a small sheltered bay on the southern side of Ynys Dewi.
This hill was not included when the original list of Pellennig hills was compiled as contemporary Ordnance Survey 1:25,000 Explorer maps do not give it any contour ring. The lack of contour rings is also applicable to the Ordnance Survey Vector Map Local hosted on the Geograph website which is entitled the Interactive Coverage Map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
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| Extract from the Ordnance Survey Vector Map Local hosted on the Geograph website |
The details for this hill were re-assessed when the OS Maps website became available online. This is the replacement for OS Get-a-map and has 5m contour intervals. This mapping gives this hill an uppermost 15m ring contour, but as this hill is adjoined to its southerly counterpart which is already listed as a Pellennig hill by a connecting bwlch higher than 5m it implies that its drop is less than the minimum 15m required for it to be considered for Pellennig status.
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| Extract from the OS Maps website |
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.
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| LIDAR image of Pt. 22.2m; 1m contour (black), 10m contour (red) and sea level (yellow) |
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| Close up LIDAR image of Pt. 22.2m; 1m contour (black), 10m contour (red) and sea level (yellow) |
The addition of this hill to Pellennig status is due to LIDAR analysis, resulting in a 22.2m summit height and confirmation that this is also its drop value as the connecting bwlch is below sea level, and with the distance between its summit and the nearest paved public road being 3.400km, it gives this hill sufficient remoteness and drop for Pellennig status.
The full details for the hill are:
Group: Carn Llidi
Name: Pt. 22.2m
OS 1:50,000 map: 157
Summit Height: 22.2m (LIDAR)
Summit Grid Reference: SM 70180 22696 (LIDAR)
Bwlch Height: N/A, sea level
Bwlch Grid Reference: N/A, sea level
Drop: 22.2m (LIDAR)
Remoteness: 3.400km
For the additions and deletions to Y Pellennig – The Remotest Hills of Wales reported on Mapping Mountains please consult the following Change Register:
Myrddyn Phillips and Aled Williams (June 2019)
© Crown: CHERISH PROJECT 2019. Produced with EU funds through the Ireland Wales Co-operation Programme 2014-2020. All material made freely available through the Open Government Licence.
Mapping Mountains - Hill Reclassifications - Y Pellennig - The Remotest Hills of Wales
Whiteford Burrows (SS 448 964) – Pellennig addition (9th reclassification)
Significant Height Revisions post for Whiteford Burrows
There has been an addition to the listing of Y Pellennig – The Remotest Hills of Wales due to LIDAR analysis initially conducted by Aled Williams and subsequently by Myrddyn Phillips.
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| LIDAR image of Whiteford Burrows |
The criteria for the list that this addition applies to are:
Y Pellennig – The Remotest Hills of Wales - Welsh hills whose summit is at least 2.5km from the nearest paved public road and the hill has a minimum 15m of drop, the list is a joint compilation between Myrddyn Phillips and Aled Williams and is available as a downloadable e-booklet or print-booklet version on Mapping Mountains Publications with the up-to-date master list available on the Mapping Mountains site in Google Doc format.
The name of the hill is Whiteford Burrows and prior to LIDAR analysis this hill was not catalogued as the uppermost contour given it on the Ordnance Survey 1:25,000 Explorer map is 5m, whilst the Ordnance Survey 1:50,000 Landranger map has no contours.
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| Extract from the Ordnance Survey 1:50,000 Landranger map |
Whiteford Burrows is adjoined to the Gŵyr group of hills, which are situated in the western part of South Wales (Region C, Sub-Region C1), and it is positioned overlooking Whiteford Point and the coast, and has the small community of Llanmadog towards the south.
As the hill is a part of designated open access land it can be approached from any direction, for those wishing to visit the Wales Coast Path approaches the hill from the south and follows land close to the coast and heads toward Whiteford Point, and the summit of the hill is only a short distance from this long distance path.
The addition of this hill to Pellennig status is due to LIDAR analysis conducted by Myrddyn Phillips. The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.
The 2m DSM LIDAR analysis gives the hill the following details:
Name: Whiteford Burrows
Summit Height: 29.6m
Summit Grid Reference: SS 44870 96422
Bwlch Height: 9.2m
Bwlch Grid Reference: SS 44631 95701
Drop: 20.4m
Therefore, the 29.6m LIDAR analysis for the summit position at SS 44870 96422 and the 9.2m LIDAR analysis for the bwlch position at SS 44631 95701 gives this hill 20.4m of drop, and with the nearest paved public road to its summit being at SS 43885 93665, it gives this hill 2.925km of remoteness which when coupled with this hill’s drop value is sufficient for Pellennig status.
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| LIDAR summit image of Whiteford Burrows |
The full details for the hill are:
Group: Gŵyr
Name: Whiteford Burrows
OS 1:50,000 map: 159
Summit Height: 29.6m (LIDAR)
Summit Grid Reference: SS 44870 96422 (LIDAR)
Bwlch Height: 9.2m (LIDAR)
Bwlch Grid Reference: SS 44631 95701 (LIDAR)
Drop: 20.4m (LIDAR)
Remoteness: 2.925km
For the additions and deletions to Y Pellennig – The Remotest Hills of Wales reported on Mapping Mountains please consult the following Change Register:
Myrddyn Phillips and Aled Williams (December 2018)
Mapping Mountains - Hill Reclassifications - Y Pellennig - The Remotest Hills of Wales
THIS HILL HAS SUBSEQUENTLY BEEN DELETED FROM PELLENNIG STATUS
There has been an addition to the listing of Y Pellennig – The Remotest Hills of Wales due to a survey conducted with the Trimble GeoXH 6000 and analysis of bwlch contouring on OS Maps, with the criteria for this list being:
Y Pellennig – The Remotest Hills of Wales - Welsh hills whose summit is at least 2.5km from the nearest paved public road and the hill has a minimum 15m of drop, the list is a joint compilation between Myrddyn Phillips and Aled Williams and is available as a downloadable e-booklet or print-booklet version on Mapping Mountains Publications with the up-to-date master list available on the Mapping Mountains site in Google Doc format.
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| Pt. 526.8m (SN 745 611) |
As the authors do not know an appropriate name for the hill it is being listed by the point (Pt. 526.8m) notation and prior to the Trimble GeoXH 6000 survey this hill was listed with c 13m of drop, based on the 527m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 514m bwlch height based on interpolation of bwlch contouring between 510m – 520m.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The hill is situated in the Elenydd group of hills which are placed in the Mid and West Wales Region (Region B, Sub-Region B2), and it is positioned in relatively remote land for Wales and has the small community of Pontrhydfendigaid towards the north-west and Tregaron towards the west.
As the hill is a part of designated open access land it can be approached from any direction, for those wishing to do so an approach from open hillside to the south is probably the most convenient as its eastern slopes are still immersed in conifer plantation.
The addition of this hill to Pellennig status is reliant upon the survey result produced by the Trimble GeoXH 6000 and interpolation of bwlch contouring on the OS Maps website. This mapping gives contour intervals at 5m and therefore narrows down the interpolated height of the bwlch, this is now estimated to be c 511m based on contouring between 510m – 515m coupled with the result of a Trimble GeoXH 6000 survey taken from near the critical bwlch, this survey produced a 511.9m height, but when doing so the authors judged land to the south-east to be lower on the hill to hill traverse, and therefore this hill is being listed with a 526.8m (converted to OSGM15) summit height and an interpolated bwlch height of c 511m, and as the nearest paved public road is 2.700km from the summit of this hill these values are sufficient for it to be classified as a Pellennig.
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| Extract from OS Maps |
The full details for the hill are:
Group: Elenydd
Summit Height: 526.8m (converted to OSGM15)
Name: Pt. 526.8m
OS 1:50,000 map: 146, 147
Summit Grid Reference: SN 74595 61119
Remoteness: 2.700km
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| The Trimble GeoXH 6000 gathering data at the summit of Pt. 526.8m |
For the additions and deletions to Y Pellennig – The Remotest Hills of Wales reported on Mapping Mountains please consult the following Change Register:
Myrddyn Phillips and Aled Williams (October 2018)
Mapping Mountains - Hill Reclassifications - Y Pellennig - The Remotest Hills of Wales
Tap Llwyd (SH 719 065) – Pellennig addition (7th reclassification)
Survey post for Tap Llwyd
There has been an addition to the listing of Y Pellennig – The Remotest Hills of Wales due to a survey with the Trimble GeoXH 6000 that was instigated by a previous basic levelling survey (BLS) and summit and bwlch spot heights that appear on the Ordnance Survey Interactive Coverage Map hosted on the Geograph website.
The criteria for qualification as a Pellennig is any Welsh hill whose summit is at least 2.5km from the nearest paved public road and the hill has a minimum 15m of drop, the list is a joint compilation between Myrddyn Phillips and Aled Williams and is available as a downloadable e-booklet or print-booklet version on Mapping Mountains Publications with the up-to-date master list available on the Mapping Mountains site in Google Doc format.
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| Tap Llwyd (SH 719 065) |
The name of the hill is Tap Llwyd and prior to the Trimble GeoXH 6000 survey this hill was not classified as it had been surveyed on the 29.09.05 by Myrddyn Phillips using the BLS method as having 44ft 6̋ / 13.6m of drop. Importantly on this day only the high point of the hill outside of its adjacent conifer plantation could be taken as its summit. Since the BLS was conducted the Ordnance Survey Interactive Coverage Map hosted on the Geograph website has become available, and this map gives this hill 15m of drop with a 566m summit and 551m bwlch spot height.
The hill is situated in the Tarennydd group of hills with its Cardinal Hill being Tarren y Gesail (SH 710 058) and is placed in the Region of North Wales (Region A, Sub-Region A3). The hill is positioned between the A 487 road to its east and the B 4405 road to its west and has the small community of Abergynolwyn towards its west, and has conifer plantations surrounding its western slopes and its lower eastern slopes.
As the designated border of open access land only takes in the open hillside and not the conifer plantation to the hill’s immediate west, permission to visit its summit should be sought, however common sense should prevail and as its high point is only a few metres in to what was felled forestry at the time of the Trimble survey, it is likely there would be no objection to its summit being visited.
Two points were surveyed with the Trimble GeoXH 6000 for summit position, the first being the high point of the hill outside the forestry and the second being the high point of the hill in what on the day of the survey was felled forestry, these surveys came to; 564.7m (converted to OSGM15) and 565.7m (converted to OSGM15) respectively, and with a bwlch height of 550.5m (converted to OSGM15), these values give this hill 15.3m of drop, and as the nearest paved public road is 2.875km from the summit of Tap Llwyd this hill meets the criteria for inclusion as a Pellennig hill.
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| The Trimble GeoXH 6000 gathering data at the summit of Tap Llwyd |
The full details for the hill are:
Cardinal Hill: Tarren y Gesail
Summit Height: 565.7m (converted to OSGM15)
Name: Tap Llwyd
OS 1:50,000 map: 124
Summit Grid Reference: SH 71990 06571
Drop: 15.3m (converted to OSGM15)
Remoteness: 2.875km
For the additions and deletions to Y Pellennig – The Remotest Hills of Wales reported on Mapping Mountains please consult the following Change Register:
For details on the survey that confirmed this hill's addition as a Pellennig
Myrddyn Phillips and Aled Williams (April 2018)
Myrddyn Phillips and Aled Williams (April 2018)
Mapping Mountains - Hill Reclassifications - Y Pellennig - The Remotest Hills of Wales
Pembrey Forest (SN 393 016) - Pellennig deletion (6th reclassification)
There has been a deletion of a hill from the list of Y Pellennig – The Remotest Hills of Wales, due to analysis of LIDAR data by Aled Williams. The criteria for qualification as a Pellennig is any hill in Wales whose summit is at least 2.5km from the nearest paved public road and the hill having a minimum drop of 15m. The list of Y Pellennig – The Remotest Hills of Wales is available as a downloadable e-booklet or print-booklet version on Mapping Mountains Publications with the up-to-date master list available on the Mapping Mountains site.
The hill is situated in the west south-western part of the Mynydd Sylen group of hills and as its name suggests; it is a part of a relatively large area of land comprising almost 2,500 acres of woodland whose south-western boundary borders sand dunes with the sea beyond. Its Cardinal Hill is Mynydd Sylen (SN 515 080) and it is placed in the Region of South Wales (C-1). The hill and conifer plantation is named the Pembrey Forest and it is situated with the community of Pen-bre and the town of Porth Tywyn (Burry Port) to its east south-east.
The hill can be accessed from one of the main forest tracks that emerge out of the Pembrey Country Park to its south-east, or from a public footpath to its north that forms a part of the Wales Coastal Path.
The name of the hill is Pembrey Forest and it was listed as a Pellennig with 2.560km distance between its summit and the nearest paved public road and with c 18m of drop. The previously listed summit is positioned at SN 390 021, this position is to one of five 25m ring contours that are shown on the Ordnance Survey 1:25,000 Explorer map, and importantly this ring contour is the furthest from any paved public road.
The deletion of Pembrey Forest from the listing of Pellennig hills 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 to the highest natural ground within the forest gives the hill the following details:
Pembrey Forest
Summit Height: 27.1m
Summit Grid Reference: SN 39390 01694
Bwlch Height: 9.5m
Bwlch Grid Reference: SN 38702 02181
Drop: 17.6m
Remoteness: 2.360km from SN 41696 02197 (does not qualify on distance)
The bwlch position given above connects this hill to the Pembrey Forest Ski Slope, which is given a much larger 25m ring contour and also a 30m ring contour; although in all probability the summit has been altered during the building of the ski slope. The critical bwlch for whichever high point is taken is positioned at SN 409 019 and is c 7m high.
The summit previously listed in the Y Pellennig list is to the north of the details to the hill given above, and its LIDAR data came to:
24.8m at SN 38984 02162
However, there is a higher summit in the vicinity of the old Pellennig summit and this hill’s details was also analysed with LIDAR data, these are given below:
Pembrey Forest
Summit Height: 25.7m
Summit Grid Reference: SN 39118 02003
Bwlch Height: 13.4m
Bwlch Grid Reference: SN 39288 01922
Drop: 12.3m (does not qualify on drop)
Aled’s analysis of LIDAR data gave the hill a 27.1m summit height at SN 39390 01694, and a 9.5m bwlch height at SN 38702 02181 (bwlch position connecting to probable artificial summit of ski slope), these values give this hill 17.6m of drop, and a 2.360km distance from the nearest paved public road which is insufficient for it to retain its Pellennig status.
This now brings the overall total for Y Pellennig to 168 hills for the Complete list (All Wales), with the total for the Mainland Wales list being 124 hills. The Master List will be duly updated on the Mapping Mountains site.
The full details for the hill are:
Cardinal Hill: Mynydd Sylen
Summit Height: 27.1m (LIDAR data)
Name: Pembrey Forest
OS 1:50,000 map: 159
Summit Grid Reference: SN 39390 01694
Drop: 17.6m (LIDAR data)
Distance: 2.360km
The list of additions and deletions in the Pellennig list since the 1st edition of Y Pellennig – The Remotest Hills of Wales was published by Europeaklist (1st edition, April 2015) is as follows:
ADDITIONS
DELETIONS
Y Pellennig – The Remotest Hills of Wales is now published by Mapping Mountains Publications (2nd edition, July 2016).
Myrddyn Phillips and Aled Williams (January 2017)
Mapping Mountains - Hill Reclassifications - Y Pellennig - The Remotest Hills of Wales
Esgair y Llyn (SN 841 701) - Pellennig addition (5th reclassification)
There has been an addition to the list of Y Pellennig – The Remotest Hills of Wales instigated from map study and confirmed by LIDAR analysis conducted by Aled Williams and a subsequent Trimble GeoXH 6000 survey conducted by Myrddyn Phillips and Aled Williams.
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| Esgair y Llyn (SN 841 701) |
The hill is situated in the Elenydd group of hills which are positioned in the central part of the Region 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 is from the east north-east via 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 featureless, and when visiting the hill a day comprising good weather is highly recommended.
The name of the hill is Esgair y Llyn and its inclusion as a Pellennig 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, these values give the hill 16m of drop which is sufficient to enter the list of Pellennig hills with the caveat of the distance from the hill’s summit to the nearest paved public road being a minimum of 2.5km. 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.
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 when coupled with its summit being 4.535km from the nearest paved public road for qualification as a Pellennig hill.
The subsequent Trimble GeoXH 6000 survey produced a summit height of 528.6m and a bwlch height of 513.0m, with these values giving this hill 15.6m of drop, which along with its remoteness is sufficient for this hill to be classified as a Pellennig.
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| The Trimble GeoXH 6000 gathering data at the summit of Esgair y Llyn |
This now brings the overall total for Y Pellennig to 169 hills for the Complete list (All Wales), with the total for the Mainland Wales list being 125 hills. The Master List will be duly updated on the Mapping Mountains site.
The full details for the hill are:
Cardinal Hill: Carny yr Hyrddod
Summit Height: 528.6m (converted to OSGM15)
Name: Esgair y Llyn
OS 1:50,000 map: 135, 136, 147
Summit Grid Reference: SN 84116 70174
Drop: 15.6m
Distance: 4.535km
The list of additions and deletions in the Pellennig list since the 1st edition of Y Pellennig – The Remotest Hills of Wales was published by Europeaklist (1st edition, April 2015) is as follows:
ADDITIONS
Esgair y Llyn (LIDAR data) (SN 841 701)
DELETIONS
Myrddyn Phillips and Aled Williams (December 2016)
Bryn Llwyd (SN 835 920) - Pellennig addition (4th reclassification)
1st Survey post and 2nd survey post for Bryn Llwyd
Significant Name Changes post for Bryn Llwyd
There has been a new hill that has entered the list of Y Pellennig – The Remotest Hills of Wales, due to a recent Trimble survey. The hill is situated in the Pumlumon group of hills in the northern part of mid Wales and is situated between the towns of Llanidloes to its south-east and Machynlleth to its north-west.
The hill was surveyed over two days on 5th and 13th May 2016, both in beautiful sunshine and its name is Bryn Llwyd. It can be accessed from the east via a track that leaves a minor road toward the farm of Nant-yr-hafod, or alternatively it can be accessed from its north via a track that leaves a minor road leading toward the lake of Glaslyn, or from a track that leaves the same minor road and makes its way around the southern flank of Y Grug. These approaches from the north have to contend with Cors yr Ebolion, which as its Welsh name suggests is a bog. If tempted by one of these northern approaches it is advisable to keep to a path that contours the eastern flank of Banc Bugeilyn before losing height to cross the reed infested stream close to the south-west corner of the conifer plantation to the north of this hill’s summit.
Bryn Llwyd was surveyed by the Trimble GeoXH 6000 as being 501.4m (converted to OSGM15, and average of four summit surveys) high, and prior to this survey the highest point listed hereabouts was Bryn yr Ŵyn which had been regarded as being higher than Bryn Llwyd and therefore listed as the summit in the 500m Twmpau list. However, Bryn yr Ŵyn was surveyed by the Trimble as being 499.9m (converted to OSGM15, and average of five summit surveys) high, and as contour interpolation and a rudimentary survey suggested that the connecting bwlch between these two hills was not low enough to give each sufficient drop to be listed as separate summits; only Bryn yr Ŵyn was previously listed. This Trimble survey confirms Bryn Llwyd to be the higher summit (see Summit Relocation post) and as the nearest paved public road at SN 84696 94288 is 2.525km from the summit this hill qualifies for the listing of Y Pellennig – The Remotest Hills of Wales, having the required 15m minimum drop and 2.5km minimum distance between the summit and the nearest paved public road.
This now brings the overall total for Y Pellennig to 168 hills for the Complete list (All Wales), with the total for the Mainland Wales list being 124 hills. The Master List will be duly updated on the Mapping Mountains site.
The full details for the hill are:
Cardinal Hill: Pumlumon Fawr
Summit Height: 501.4m (converted to OSGM15, and average of four summit surveys)
Name: Bryn Llwyd
OS 1:50,000 map: 135, 136
Summit Grid Reference: SN 83574 92022
Drop: 30.3m (converted to OSGM15)
Distance: 2.525km
The list of additions and deletions in the Pellennig list since the 1st edition of Y Pellennig – The Remotest Hills of Wales was published by Europeaklist is as follows:
ADDITIONS
Bryn Llwyd (SN 835 920) 1st survey, 2nd survey
DELETIONS
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| Bryn Llwyd (SN 835 920) now confirmed as a Pellennig hill |
For details on the 1st Trimble survey and the 2nd Trimble survey that promoted this hill to Pellennig status.
Myrddyn Phillips and Aled Williams (May 2016)
Mapping Mountains - Hill Reclassifications - Y Pellennig - The Remotest Hills of Wales
Graig Fach (SN 821 930) - Pellennig deletion (3rd reclassification)
1st Survey post for Graig Fach
2nd Survey post for Graig Fach
There has been a deletion of a hill from the list of Y Pellennig – The Remotest Hills of Wales, due to a survey with the Trimble GeoXH 6000. The hill is situated in the Pumlumon group in northern mid Wales and is situated between the towns of Machynlleth to its north-west and Llanidloes to its south-east with the mountain lakes of Glaslyn to its north and Bugeilyn to its south.
The name of the hill is Graig Fach and it was surveyed over two days; 5th May 2016 and 22nd February 2019, both in beautiful early morning sunshine. The hill can be easily accessed from the north via the track that leaves a minor road toward the lake of Glaslyn, or alternatively a longer approach to the hill is from the south-west following the path above the course of the Afon Hengwm.
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.
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 on both days, whilst the summit consists of a small rock and grassy knoll with five data sets taken in all from the area of the summit, resulting in the hill only having 14.7m of drop and therefore below the 15m minimum drop value required to qualify for this list. This hill is a loss to the Pellennig listing as it is one that must be seldom visited and affords good views across to the expanse of wilderness situated around Llechwedd Crin and Banc Bugeilyn.
This now brings the overall total for Y Pellennig to 167 hills for the Complete list (All Wales), with the total for the Mainland Wales list also decreasing by one to 123 hills. The Master List will be duly updated on the Mapping Mountains site.
This now brings the overall total for Y Pellennig to 167 hills for the Complete list (All Wales), with the total for the Mainland Wales list also decreasing by one to 123 hills. The Master List will be duly updated on the Mapping Mountains site.
The full details for the hill are:
Cardinal Hill: Foel Fadian
Summit Height: 513.5m (converted to OSGM15)
Name: Graig Fach
OS 1:50,000 map: 135, 136
Summit Grid Reference: SN 82117 93069
Drop: 14.7m (converted to OSGM15)
The list of additions and deletions in the Pellennig list since the 1st edition of Y Pellennig – The Remotest Hills of Wales was published by Europeaklist is as follows:
ADDITIONS
DELETIONS
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| Graig Fach (SN 821 930) now deleted from the Y Pellennig list |
Myrddyn Phillips and Aled Williams (May 2016)
Mapping Mountains - Hill Reclassifications - Y Pellennig - The Remotest Hills of Wales
Ynys Arw (SH 266 945) - Pellennig addition (2nd reclassification)
Survey post for Ynys Arw
Significant Height Revisions post for Ynys Arw
There has been a new hill that has entered the list of Y Pellennig – The Remotest Hills of Wales, due to a recent Trimble survey. The hill is situated on Ynysoedd y Moelrhoniaid, this small group of islands are positioned to the north-west, off the north-west coast of Ynys Môn; its name is Ynys Arw.
Ynys Arw (SH 266 945) is the most south-westerly island of this archipelago and has two high points, with the more southerly of these being the highest. Ynys Arw is tidal and is connected by land to its higher neighbour at low tide, the higher island is where The Skerries Lighthouse is situated and is the highest point of the archipelago and is also listed as a Pellennig hill.
The summit of Ynys Arw is easily accessed at low tide from the Lighthouse, although hands on rock are required to get down to the connecting land that is submerged at high tide. The ascent from this wet sea weeded land is on rock and then grass that has a multitude of burrowed Tern nests excavated into it.
The high point of Ynys Arw has a 10m ring contour on it and no spot height on current Ordnance Survey maps, it was surveyed with the Trimble GeoXH 6000 at being 15.2m (converted to OSGM15) high, and as the criteria for qualification to the Pellennig list is a hill whose summit is a minimum of 2.5 km from the nearest paved public road and which has a minimum drop of 15m, this hill easily qualifies on the distance criterion and now meets the necessary minimum drop criterion to become the latest entry to the Pellennig list.
This now brings the overall total for Y Pellennig to 168 hills for the Complete list (All Wales), with the total for the Mainland Wales list remaining the same at 124 hills. The Master List will be duly updated on the Mapping Mountains site.
The full details for the hill are:
Cardinal Island: Ynysoedd y Moelrhoniaid
Summit Height: 15.2m (converted to OSGM15, Trimble GeoXH 6000)
Name: Ynys Arw
OS 1:50,000 map: 114
Summit Grid Reference: SH 26647 94598 (Trimble GeoXH 6000)
Drop: 15.2m (Trimble GeoXH 6000 summit and LIDAR bwlch)
The list of additions in the Y Pellennig list since the 1st edition of Y Pellennig – The Remotest of Wales was published by Europeaklist is as follows:
ADDITIONS
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| Ynys Arw (SH 266 945) - the new Pellennig hill |
For details on the survey that promoted this hill to Pellennig status please click {here}
©
Crown: CHERISH PROJECT 2019. Produced with EU funds through the Ireland Wales
Co-operation Programme 2014-2020. All material made freely available through
the Open Government Licence.
Myrddyn Phillips and Aled Williams (September 2015)
Mapping Mountains - Hill Reclassifications - Y Pellennig - The Remotest Hills of Wales
Pen Diban (SH 112 205) - Pellennig addition (1st reclassification)
Survey post for Pen Diban
There has been a re-instatement of a Pellennig hill due to a recent Trimble survey. The hill is situated on Ynys Enlli and is positioned at the south of the island; its name is Pen Diban.
Pen Diban (SH 112 205) was included in the original list of Y Pellennig that was published on Geoff Crowder’s v-g.me website and listed with a 20m high summit and a c 5m high bwlch, giving a drop of c 15m. The drop was estimated and based on contour interpolation with the Ordnance Survey 1:25,000 paper maps having 10m contour intervals.
Since the original publication of Y Pellennig, the Ordnance Survey enlarged mapping on the Geograph website has become available; this mapping for the area where Pen Diban is situated gives contour intervals at 5m and narrows the area and the height of the bwlch to c 5m – c 10m. Therefore the drop of Pen Diban was re-evaluated as c 14m and it was deleted from the ranks of Y Pellennig – The Remotest Hills of Wales.
This hill has now been surveyed with the Trimble GeoXH 6000, its surveyed summit height is 20.0m (converted to OSGM15) and its surveyed bwlch height is 5.0m (converted to OSGM15).
The raw processed survey result for the summit is 19.975m converted to OSGM15
The raw processed survey result for the bwlch is 4.982m converted to OSGM15
The margin of uncertainty for the height in relation to the position of the Trimble on the summit is 0.0m and for the bwlch 0.05m.
The precision of the equipment is +/- 0.15m.
The accuracy of the equipment is 0.1m.
Therefore the raw result for the drop should be rounded to one decimal place; 15.0m
This now brings the overall total for Y Pellennig to 167 hills for the Complete list (All Wales), with the total for the Mainland Wales list remaining the same at 124 hills. The Master List will be duly updated on the Mapping Mountains blog.
The full details for the hill are:
Cardinal Island: Ynys Enlli
Summit Height: 20.0m (converted to OSGM15)
Name: Pen Diban
OS 1:50,000 map: 123
Summit Grid Reference: SH 112 205
Drop: 15.0m (converted to OSGM15)
.jpg) |
| Pen Diban (SH 112 205) the re-instated Pellennig hill |
For details on the survey that promoted this hill to Pellennig status please click {here}
Myrddyn Phillips and Aled Williams (April 2015)
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