Mapping Mountains - Hill Reclassifications - Y Pellennig - The Remotest Hills of Wales
Pt. 526.8m (SN 745 611) – Pellennig deletion(12th reclassification)
Survey post for Pt. 526.8m
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:
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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.
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| 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)
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:
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). |
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:
Summit Height: 16.4m (LIDAR)
Summit Grid Reference: SM 70552 22500 (LIDAR)
Bwlch Height: 0.8m (LIDAR)
Bwlch Grid Reference: SM 70545 22512 (LIDAR)
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.
Mapping Mountains - Hill Reclassifications - Y Pellennig - The Remotest Hills of Wales
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:
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:
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
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:
Summit Grid Reference: SS 44870 96422
Bwlch Grid Reference: SS 44631 95701
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:
Summit Height: 29.6m (LIDAR)
Summit Grid Reference: SS 44870 96422 (LIDAR)
Bwlch Height: 9.2m (LIDAR)
Bwlch Grid Reference: SS 44631 95701 (LIDAR)
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:
Summit Height: 526.8m (converted to OSGM15)
OS 1:50,000 map: 146, 147
Summit Grid Reference: SN 74595 61119
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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:
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
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)
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