100m
Twmpau – Summit Relocations
The 100m Twmpau (thirty welsh metre prominences and upward) are the Welsh hills at or above 100m
and below 200m in height that have a minimum drop of 30m. Accompanying the main P30 list is a sub list
entitled the 100m Sub-Twmpau with the
qualification to 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.
The list is authored by Myrddyn
Phillips and the posts that have appeared on Mapping Mountains detailing the
summit relocations to the main P30 list and the sub list appear below presented
chronologically in receding order.
Mapping Mountains - Summit Relocations - 100m Twmpau
Y Grongaer (SN 573 215 & SN 574 215) - 35th summit relocation
Significant Height Revisions post for Y Grongaer
There has been a Summit Relocation 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.
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| LIDAR image of Y Grongaer (SN 573 215 & SN 574 215) |
The criteria for the two listings that this summit relocation 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.
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| 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 3rd December 2015, and the list is now available in its entirety on Mapping Mountains in Google Doc format.
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| Y Trechol - The Dominant Hills of Wales by Myrddyn Phillips |
The name the hill is listed by is Y Grongaer, and it is adjoined to the Mynydd Mallaen group of hills, which are situated in the central part of South Wales (Region B, Sub-Region B1), and it is positioned with the A40 road to its north, the B4297 road to its west, the B4300 road to its south and a minor road to its east, and has the town of Llandeilo towards the east.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website, this hill was listed with a 143m summit height, based on the spot height that is positioned at SN 57326 21596 and appears on the Ordnance Survey 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
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 summit image of Y Grongaer (SN 573 215 & SN 574 215) |
The summit height produced by LIDAR analysis is 140.7m and is positioned at SN 57399 21574 and SN 57400 21575, and this comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to when the high point is positioned in a different field, to a different feature such as a conifer plantation, within a different map contour, a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.
Therefore, the summit height produced by LIDAR analysis is 140.7m and is positioned at SN 57399 21574 and SN 57400 21575, this position is not given a spot height on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, and is approximately 75 metres eastward and placed in a different ring contour from where the previously listed summit is positioned.
The full details for the hill are:
Group: Mynydd Mallaen
Name: Y Grongaer
OS 1:50,000 map: 159
Summit Height: 140.7m (LIDAR)
Summit Grid Reference (New Position): SN 57399 21574 & SN 57400 21575 (LIDAR)
Bwlch Height: 53.05m (LIDAR)
Bwlch Grid Reference: SN 57923 22123 (LIDAR)
Drop: 87.6m (LIDAR)
Dominance: 62.29% (LIDAR)
Myrddyn Phillips (April 2022)
Mapping Mountains - Summit Relocations - 100m Twmpau
Bron y Gaer (SN 699 326) - 34th summit relocation
Hill Reclassifications post for Bron y Gaer
Significant Name Changes post for Bron y Gaer
There has been confirmation of a Summit Relocation to a hill that is listed in the 100m Twmpau, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Bron y Gaer (SN 699 326) |
The criteria for the list that this summit relocation 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.
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| The 100m Twmpau by Myrddyn Phillips |
The name the hill is listed by is Bron y Gaer and this was derived from the Tithe map, and it is adjoined to the Mynydd Mallaen group of hills, which are situated in the central part of South Wales (Region B, Sub-Region B1), and it is positioned with minor roads to its west and south, the A40 road farther to its south and the A482 road to its east, and has the town of Llanymddyfri (Llandovery) towards the east north-east.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website, this hill was listed with a 198m summit height positioned at SN 697 328, based on the spot height that appears on the Ordnance Survey 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online. Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website. Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current and digitally updated such as the interactive mapping on the Magic Maps and WalkLakes websites.
The details for this hill were re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map became available online. This mapping had many spot heights not on other publicly available Ordnance Survey maps and for this hill it had a 199m summit spot height positioned at SN 69968 32669, therefore the listed summit position of this hill was relocated.
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 summit image of Bron y Gaer (SN 699 326) |
The summit height produced by LIDAR analysis is 199.7m and is positioned at SN 69948 32662 and SN 69950 32662, and this comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to when the high point is positioned in a different field, to a different feature such as a conifer plantation, within a different map contour, a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.
Therefore, the summit height produced by LIDAR analysis is 199.7m and is positioned at SN 69948 32662 and SN 69950 32662, this position is not given a spot height on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, and is approximately 270 metres south-eastward from where the previously listed summit is positioned.
The full details for the hill are:
Group: Mynydd Mallaen
Name: Bron y Gaer
OS 1:50,000 map: 146, 160
Summit Height: 199.7m (LIDAR)
Summit Grid Reference (New Position): SN 69948 32662 & SN 69950 32662 (LIDAR)
Bwlch Height: 166.5m (LIDAR)
Bwlch Grid Reference: SN 69362 32822 (LIDAR)
Drop: 33.2m (LIDAR)
Myrddyn Phillips (April 2022)
Mapping Mountains - Summit Relocations - 100m Twmpau
Y Gaer (SJ 204 155) - 33rd summit relocation
There has been a Summit Relocation to a hill that is listed in the 100m Twmpau, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis and a subsequent Trimble GeoXH 6000 survey conducted by Myrddyn Phillips.
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| Y Gaer (SJ 204 155) |
The criteria for the list that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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| The 100m Twmpau by Myrddyn Phillips |
The name the hill is listed by is Y Gaer, and it is adjoined to the Carnedd Wen group of hills which are situated in the south-eastern part of North Wales (Region A, Sub-Region A4), and it is positioned with minor roads encircling it, the A495 road farther to its north and the A490 road farther to its west, and has the village of Meifod towards the west south-west.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website, this hill was listed with a c 125m summit height positioned at SJ 204 155 with an accompanying note stating; Two points of same height. Height from Explorer 240.
As this note implies the Ordnance Survey 1:25,000 Explorer map gives two points with uppermost 125m contours without any specific spot heights, the larger of these contours is positioned at SJ 204 155 and this is where the prioritised summit of this hill was given, with the smaller contour positioned at SJ 207 156.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
As the name of this hill implies it has the remains of an ancient hill fort on its summit area which takes in a part of the larger 125m uppermost contour. Just to the east of the remains of the hill fort is a small covered reservoir which consists of steepened grassed sides leading to a breeze block construction. The natural ground of the hill is at the base of the steepened grassed sides, with these forming a part of the covered reservoir.
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| Gathering data during the first survey at the top of the steepened grass section |
The summit of this hill has been surveyed with the Trimble GeoXH 6000 on two occasions. The first when data were collected from the top of the steepened grass at the base of the breeze block section. As this constitutes a part of the covered reservoir which is deemed a relatively recent man-made construct and therefore should not be taken as a part of this hill’s height, the summit was re-surveyed.
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| Gathering data during the second survey at the highest remaining natural ground at the base of the steepened grass section |
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| Gathering data during the third survey at the high point of the ancient hill fort |
During the re-survey two points were surveyed, one at the highest remaining natural ground at the base of the steepened grass and the second at the high point of the remains of the ancient hill fort. These and the result from the first survey are given below:
08.08.15 - 1st survey, top of steepened grass section of covered reservoir: 130.450m at SJ 20413 15563
02.07.21 - 2nd survey, highest natural ground at base of steepened grass: 129.325m at SJ 20417 15566
02.07.21 - 3rd survey, highest part of ancient hill fort: 128.893m at SJ 20391 15555
Between the 08.08.15 and 02.07.21 LIDAR became available and therefore 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 summit image of Y Gaer (SJ 204 155) |
The result produced by LIDAR analysis confirmed the position of the high part of the ancient hill fort and the approximate position of the highest remaining natural ground of this hill, and as these two points have now been surveyed with the Trimble GeoXH 6000 it is this result that is being prioritised for listing purposes, and this comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to when the high point is positioned in a different field, to a different feature such as a conifer plantation, within a different map contour, a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is considered a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.
Therefore, the summit height produced by the Trimble GeoXH 6000 survey is 129.3m and this is positioned at SJ 20417 15566, this is the remaining natural high point of the hill and not ground at the top of the steepened grass, which forms a part of the covered reservoir and which is considered a relatively recent man-made construct and therefore discounted from the height of the hill.
The full details for the hill are:
Group: Carnedd Wen
Name: Y Gaer
OS 1:50,000 map: 126
Summit Height: 129.3m (converted to OSGM15, Trimble GeoXH 6000)
Summit Grid Reference (New Position): SJ 20417 15566 (Trimble GeoXH 6000)
Bwlch Height: 91.2m (LIDAR)
Bwlch Grid Reference: SJ 21177 15977 (LIDAR)
Drop: 38.2m (Trimble GeoXH 6000 summit and LIDAR bwlch)
Myrddyn Phillips (September 2021)
Mapping Mountains - Summit Relocations - 100m Twmpau
Cefn Cyfronydd (SJ 144 082) - 32nd summit relocation
Survey post for Cefn Cyfronydd
Hill Reclassifications post for Cefn Cyfronydd
Significant Name Changes post for Cefn Cyfronydd
There has been a Summit Relocation to a hill that is now listed in the 100m Twmpau, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis and a subsequent Trimble GeoXH 6000 survey conducted by Myrddyn Phillips.
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| Cefn Cyfronydd (SJ 144 082) on the left of photo |
The criteria for the list that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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| The 100m Twmpau by Myrddyn Phillips |
The name the hill is listed by is Cefn Cyfronydd and this was derived from local enquiry, and it is adjoined to the Carnedd Wen group of hills which are situated in the south-eastern part of North Wales (Region A, Sub-Region A4), and it is positioned with a minor road to its north, the B4389 road to its north-west, the A458 road to its south-west and the B4392 road to its east, and has the small town of Llanfair Caereinion towards the west south-west.
When the original Welsh 200m P30 list was published on Geoff Crowder’s v-g.me website the height of the prioritised summit of this hill was estimated as c 200m and positioned at SJ 146 084, with an accompanying note stating; Two points of same height – other at SJ 144 083, with both heights based on interpolation of the two uppermost 200m ring contours that appear on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
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 summit image of Cefn Cyfronydd |
The result produced by LIDAR analysis confirms the summit of this hill as under 200m in height and gives the previously listed non-prioritised summit as the higher, and as this summit has now been surveyed with the Trimble GeoXH 6000 it is this result that is being prioritised for listing purposes, and this comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies when the hill’s high point is found to be positioned; in a different field, to a different feature such as in a conifer plantation, placed within a different map contour, to a different point where a number of potential summit positions are within close proximity, or when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.
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| The Trimble GeoXH 6000 gathering data at the summit of Cefn Cyfronydd |
Therefore, the summit height produced by the Trimble GeoXH 6000 survey is 199.1m and this is positioned at SJ 14459 08297, this is approximately 190 metres south-westward from where the previously prioritised summit is positioned.
The full details for the hill are:
Group: Carnedd Wen
Name: Cefn Cyfronydd
OS 1:50,000 map: 125
Summit Height: 199.1m (converted to OSGM15, Trimble GeoXH 6000)
Summit Grid Reference (New Position): SJ 14459 08297 (Trimble GeoXH 6000)
Bwlch Height: 150.6m (LIDAR)
Bwlch Grid Reference: SJ 14997 08587 (LIDAR)
Drop: 48.5m (Trimble GeoXH 6000 summit and LIDAR bwlch)
Myrddyn Phillips (July 2021)
Mapping Mountains - Summit Relocations - 100m Twmpau
Penlan (SN 595 863) - 31st summit relocation
Significant Name Changes post for Penlan
There has been a Summit Relocation 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.
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| LIDAR image of Penlan (SN 595 863) |
The criteria for the two listings that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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| The 100m Twnpau 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 3rd December 2015, and the list is now available in its entirety on Mapping Mountains in Google Doc format.
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| Y Trechol - The Dominant Hills of Wales by Myrddyn Phillips |
The name the hill is listed by is Penlan and this was derived from the Tithe map, and it is adjoined to the Pumlumon group of hills, which are situated in the north-western part of Mid and West Wales (Region B, Sub-Region B2), and it is positioned with the coast to its west, a minor road to its south and the B4572 road to its east, and has the village of Llangorwen towards the south.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website this hill was listed with a 137m summit height based on the spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and which is positioned at SN 59517 86313.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
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.
LIDAR analysis indicates that the highest point of this hill is 137.6m and is placed on a raised field boundary positioned at SN 59523 86321. As raised field boundaries are considered relatively recent man-made constructs they are discounted from the height of a hill in listings that I am associated with, and it is the remaining natural summit or highest remaining natural ground that is then taken as the summit height. LIDAR analysis indicates the natural summit is intact and is 137.4m in height and positioned at SN 59521 86313, and this comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies when the hill’s high point is found to be positioned; in a different field, to a different feature such as in a conifer plantation, placed within a different map contour, to a different point where a number of potential summit positions are within close proximity, or when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.
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| LIDAR summit image of Penlan (SN 595 863) |
Therefore, the summit height produced by LIDAR analysis is 137.4m and this is positioned at SN 59521 86313, this is approximately 8 metres southward from where the highest point of the raised field boundary is positioned.
The full details for the hill are:
Group: Pumlumon
Name: Penlan
OS 1:50,000 map: 135
Summit Height: 137.4m (LIDAR)
Summit Grid Reference (New Position): SN 59521 86313 (LIDAR)
Bwlch Height: 83.8m (LIDAR)
Bwlch Grid Reference: SN 59661 86697 (LIDAR)
Drop: 53.6m (LIDAR)
Dominance: 39.01% (LIDAR)
Myrddyn Phillips (June 2021)
Mapping Mountains - Summit Relocations - 100m Twmpau
Banc Uchaf (SN 617 743) - 30th summit relocation
Significant Name Changes post for Banc Uchaf
There has been a Summit Relocation to a hill that is listed in the 100m Twmpau, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis and a subsequent Trimble GeoXH 6000 survey conducted by Myrddyn Phillips.
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| Banc Uchaf (SN 617 743) |
The criteria for the list that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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| The 100m Twmpau by Myrddyn Phillips |
The name the hill is now listed by is Banc Uchaf and this was derived from the Tithe map, and it is adjoined to the Elenydd group of hills which are situated in the western part of Mid and West Wales (Region B, Sub-Region B2), and it is positioned with the A485 road to its north and minor roads to its west, south and east, and has the village of Llanilar towards the north north-east.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website this hill was listed with a 197m summit height based on the spot height that appears on the Ordnance Survey 1:25,000 Explorer map and which is positioned at SN 61731 74185.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
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 summit image of Banc Uchaf |
LIDAR analysis indicated a summit relocation for this hill and as the summit has subsequently been surveyed with the Trimble GeoXH 6000 it is this result that is being prioritised for listing purposes, resulting in a summit height of 197.6m positioned at SN 61768 74325 and this height and its position comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies when the hill’s high point is found to be positioned; in a different field, to a different feature such as in a conifer plantation, placed within a different map contour, to a different point where a number of potential summit positions are within close proximity, or when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.
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| The Trimble GeoXH 6000 gathering data at the summit of Banc Uchaf |
Therefore, the new listed summit height for this hill is 197.6m and is positioned at SN 61768 74325, this position is not given a spot height on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and is approximately 140 metres northward from where the summit was originally listed which was to the position of the 197m spot height that appears on the Ordnance Survey 1:25,000 Explorer map.
The full details for the hill are:
Group: Elenydd
Name: Banc Uchaf
OS 1:50,000 map: 135
Summit Height: 197.6m (converted to OSGM15, Trimble GeoXH 6000)
Summit Grid Reference (New Position): SN 61768 74325 (Trimble GeoXH 6000)
Bwlch Height: 148.5m (LIDAR)
Bwlch Grid Reference: SN 61371 72717 (LIDAR)
Drop: 49.1m (Trimble GeoXH 6000 summit and LIDAR bwlch)
Myrddyn Phillips (May 2021)
Mapping Mountains - Summit Relocations - 100m Twmpau
Banc (SN 568 757) - 29th summit relocation
Significant Height Revisions post for Banc
Significant Name Changes post for Banc
There has been a Summit Relocation to a hill that is listed in the 100m Twmpau, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis and a subsequent Trimble GeoXH 6000 survey conducted by Myrddyn Phillips.
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| Banc (SN 568 757) |
The criteria for the list that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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| The 100m Twmpau by Myrddyn Phillips |
The name the hill is now listed by is Banc and this was derived from the Tithe map, and it is adjoined to the Elenydd group of hills which are situated in the western part of Mid and West Wales (Region B, Sub-Region B2), and it has the coast to its west and the A487 road to its east, and has the village of Llanfarian towards the north-east.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website this hill was listed with a 192m summit height based on the spot height adjoined to a triangulation pillar that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and which is positioned at SN 56695 75938.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were subsequently re-assessed against a number of Ordnance Survey maps made available online, including the Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, the interactive mapping available on the WalkLakes website as well as the Magic Maps website and none showed further detail other than the 192m spot height adjoined to the triangulation pillar.
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 Banc (SN 568 757) |
The summit of this hill has now been surveyed with the Trimble GeoXH 6000 and this is being prioritised in preference to the LIDAR height and position, resulting in 194.2m at SN 56817 75750 and this height and its position comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies when the hill’s high point is found to be positioned; in a different field, to a different feature such as in a conifer plantation, placed within a different map contour, to a different point where a number of potential summit positions are within close proximity, or when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.
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| The Trimble GeoXH 6000 gathering data at the summit of Banc with the previously listed summit in the background |
Therefore, the new listed summit height for this hill is 194.2m and is positioned at SN 56817 75750, this position is not given a spot height on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and is approximately 200 metres south-eastward from where the summit was originally listed which was to the position of the 192m spot height adjoined to the triangulation pillar.
The full details for the hill are:
Group: Elenydd
Name: Banc
OS 1:50,000 map: 135
Summit Height: 194.2m (converted to OSGM15, Trimble GeoXH 6000)
Summit Grid Reference (New Position): SN 56817 75750 (Trimble GeoXH 6000)
Bwlch Height: 130.2m (LIDAR)
Bwlch Grid Reference: SN 57845 73062 (LIDAR)
Drop: 64.0m (Trimble GeoXH 6000 summit and LIDAR bwlch)
Myrddyn Phillips (March 2021)
Mapping Mountains - Summit Relocations - 100m Twmpau
Banc Tŷ Hen (SN 650 895) - 28th summit relocation
There has been a Summit Relocation 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.
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| LIDAR image of Banc Tŷ Hen (SN 650 895) |
The criteria for the two listings that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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| 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 3rd December 2015, and the list is now available in its entirety on Mapping Mountains in Google Doc format.
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| Y Trechol - The Dominant Hills of Wales by Myrddyn Phillips |
The name the hill is listed by is Banc Tŷ Hen and it is adjoined to the Pumlumon group of hills, which are situated in the north-western part of Mid and West Wales (Region B, Sub-Region B2), and it is positioned with minor roads to its north and west and the A487 road and the Afon Leri to its south-east, and has the small community of Tal-y-bont towards the south-east.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website this hill was listed with a 157m summit height based on the spot height that appears on the Ordnance Survey 1:25,000 Explorer map and which is positioned at SN 64770 89387.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online. This mapping had many spot heights not on other publicly available Ordnance Survey maps and gives a second 157m spot height on the area of this hill’s summit positioned at SN 65036 89542.
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.
The summit height produced by LIDAR analysis is 157.4m and is positioned at SN 65012 89554. When compared to the original listed summit position the above detail comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies when the hill’s high point is found to be positioned; in a different field, to a different feature such as in a conifer plantation, placed within a different map contour, to a different point where a number of potential summit positions are within close proximity, or when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.
Therefore, the summit height produced by LIDAR analysis is 157.4m and this is positioned at SN 65012 89554, this is approximately 300 metres north-eastward from where the original listed summit was given which was to the position of the 157m spot height on the Ordnance Survey 1:25,000 Explorer map.
The full details for the hill are:
Group: Pumlumon
Name: Banc Tŷ Hen
OS 1:50,000 map: 135
Summit Height: 157.4m (LIDAR)
Summit Grid Reference (New Position): SN 65012 89554 (LIDAR)
Bwlch Height: 63.7m (LIDAR)
Bwlch Grid Reference: SN 65510 89668 (LIDAR)
Drop: 93.6m (LIDAR)
Dominance: 59.49% (LIDAR)
Myrddyn Phillips (April 2021)
Mapping Mountains - Summit Relocations - 100m Twmpau
Chepstow Hill (ST 355 905) - 27th summit relocation
Significant Height Revisions post for Chepstow Hill
Chepstow Hill (ST 355 905) - 27th summit relocation
Significant Height Revisions post for Chepstow Hill
There has been a Summit Relocation 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 confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Chepstow Hill (ST 355 905) |
The criteria for the two listings that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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 3rd December 2015, and the list is now available in its entirety on Mapping Mountains in Google Doc format.
The name the hill is listed by is Chepstow Hill and it is adjoined to the Gwent Is Coed group of hills which are situated in the south-eastern part of South Wales (Region C, Sub-Region C3), and it is positioned with the Afon Wysg (River Usk) to its north-west, the M4 motorway to its south and the A449 road to its east, and has the city of Casnewydd (Newport) towards the south-west.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website this hill was listed with a 111m summit height based on the spot height that appears on the Ordnance Survey 1:25,000 Explorer map and which is positioned at ST 36372 91144.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online. This mapping had many spot heights not on other publicly available Ordnance Survey maps and gives a 114m spot height on the summit area of this hill and positioned at ST 35626 90589. This 114m spot height also appears on Ordnance Survey data available on the Magic Maps website.
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| Extract from the Magic 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 summit image for Chepstow Hill |
The summit height produced by LIDAR analysis is 116.6m and is positioned at ST 35547 90567. The above detail comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when it is positioned to a different feature such as in a conifer plantation, or when the high point of the hill is placed within a different map contour compared to its previous listed position, or when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct.
Therefore, the summit height produced by LIDAR analysis is 116.6m and this is positioned at ST 35547 90567, this is approximately 1000 metres south-westward from where the originally listed summit position was given which was to the position of the 111m spot height.
The full details for the hill are:
Group: Gwent Is Coed
Name: Chepstow Hill
OS 1:50,000 map: 171
Summit Height: 116.6m (LIDAR)
Summit Grid Reference (new position): ST 35547 90567 (LIDAR)
Bwlch Height: 63.2m (LIDAR)
Bwlch Grid Reference: ST 36979 90843 (LIDAR)
Drop: 53.4m (LIDAR)
Dominance: 45.76% (LIDAR)
Myrddyn Phillips (July 2020)
Coed Anghred Hill (SO 457 194) - 26th summit relocation
Significant Height Revisions post for Coed Anghred Hill
There has been a Summit Relocation 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 confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Coed Anghred Hill (SO 457 194) |
The criteria for the two listings that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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 3rd December 2015, and the list is now available in its entirety on Mapping Mountains in Google Doc format.
The name the hill is listed by is Coed Anghred Hill and it is adjoined to the Mynyddoedd Duon group of hills which are situated in the eastern part of South Wales (Region C, Sub-Region C3), and it is positioned with the Afon Mynwy (River Monnow) and the B4521 road to its north and the B4347 road to its west, and has the small village of Ynysgynwraidd (Skenfrith) towards the north.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website this hill was listed with a 192m summit height based on the spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and which is positioned at SO 45823 19468.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-evaluated when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online, and as this map gives no further details the summit location remained the same.
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 summit image of Coed Anghred Hill |
The summit height produced by LIDAR analysis is 198.8m positioned at SO 45713 19487. The above detail comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when it is positioned to a different feature such as in a conifer plantation, or when the high point of the hill is placed within a different map contour compared to its previous listed position, or when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct.
Therefore, the summit height produced by LIDAR analysis is 198.8m and this is positioned at SO 45713 19487, this is approximately 110 metres westward from where the previously listed summit position was given to the 192m spot height.
The full details for the hill are:
Group: Mynyddoedd Duon
Name: Coed Anghred Hill
OS 1:50,000 map: 161
Summit Height: 198.8m (LIDAR)
Summit Grid Reference (new position): SO 45713 19487 (LIDAR)
Bwlch Height: 128.8m (LIDAR)
Bwlch Grid Reference: SO 44881 19181 (LIDAR)
Drop: 70.0m (LIDAR)
Dominance: 35.20% (LIDAR)
Myrddyn Phillips (March 2020)
Mapping Mountains - Summit Relocations - 100m Twmpau
Trostrey Hill (SO 369 051) - 25th summit relocation
There has been a Summit Relocation 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 confirmed by LIDAR analysis conducted by Myrddyn Phillips.
%20-%20LIDAR%20hill%201.jpg) |
| LIDAR image of Trostrey Hill (SO 369 051) |
The criteria for the two listings that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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| 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 3rd December 2015, and the list is now available in its entirety on Mapping Mountains in Google Doc format.
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| Y Trechol - The Dominant Hills of Wales by Myrddyn Phillips |
The name the hill is listed by is Trostrey Hill and it is adjoined to the Mynyddoedd Duon group of hills which are situated in the eastern part of South Wales (Region C, Sub-Region C3), and it is positioned with the Afon Wysg (River Usk) and the B4598 road to its west, the A40 road to its north, the A472 road to its south and the A449 road to its east, and has the village of Raglan towards the east north-east and the town of Brynbuga (Usk) towards the south.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website this hill was listed with a 199m summit height based on the spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and which is adjoined to a triangulation pillar positioned at SO 36917 05185.
%20-%201%2025000.jpg) |
| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-evaluated when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online, and as this map gives no further details the summit location remained the same.
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%20summit%202.jpg) |
| LIDAR summit image of Trostrey Hill (SO 369 051) |
The summit height produced by LIDAR analysis to remaining natural ground is 199.3m positioned at SO 36920 05188 with LIDAR also giving a 199.5m height positioned at SO 36920 05184 to a raised field boundary that is excluded from the height of this hill as it is considered a recent man-made construct. The above detail comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when it is positioned to a different feature such as in a conifer plantation, or when the high point of the hill is placed within a different map contour compared to its previous listed position, or when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct.
Therefore, the summit height produced by LIDAR analysis is 199.3m to ground meeting the criteria used within this list and this is positioned at SO 36920 05188, this is approximately 4 metres from where LIDAR gives the high point of the raised field boundary, but as this is considered a relatively recent man-made construct it is not taken as a part of the height of this hill.
The full details for the hill are:
Group: Mynyddoedd Duon
Name: Trostrey Hill
OS 1:50,000 map: 161
Summit Height: 199.3m (LIDAR)
Summit Grid Reference (New Position): SO 36920 05188 (LIDAR)
Bwlch Height: 129.1m (LIDAR)
Bwlch Grid Reference: SO 37462 05935 (LIDAR)
Drop: 70.2m (LIDAR)
Dominance: 35.23% (LIDAR)
Myrddyn Phillips (March 2020)
Mapping Mountains - Summit Relocations - 100m Twmpau
Wenvoe Quarry (ST 131 741) - 24th summit relocation
Significant Name Changes post for Wenvoe Quarry
Significant Height Revisions post for Wenvoe Quarry
There has been a Summit Relocation to a hill that is listed in the 100m Twmpau and Y Trechol – The Dominant Hills of Wales, with the summit height and its position confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR summit image of Wenvoe Quarry (ST 131 741) |
The criteria for the two listings that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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 3rd December 2015.
The name the hill is now listed by is Wenvoe Quarry and it is adjoined to the Bro Morgannwg group of hills, which are situated in the southern part of South Wales (Region C, Sub-Region C2), and it is positioned with a number of A roads encircling it with the A4232 to its north and east, the A4050 to its west and the A4055 further to its south-east, and has the city of Caerdydd (Cardiff) towards the north-east.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website this hill was listed with a c 115m summit height positioned at ST 132 742, based on the uppermost contour on contemporary Ordnance Survey 1:25,000 Explorer maps.
When this 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 117m summit height based on interpolation of the uppermost 115m contour on the Ordnance Survey 1:25,000 Explorer map, with this summit height later being changed to an estimated c 118m and with its summit position listed as ST 130 742.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
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.
The height produced by LIDAR analysis is 123.4m and is positioned at ST 13189 74189, and the above detail comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct.
Therefore, the summit height produced by LIDAR analysis is 123.4m and this is positioned at ST 13189 74189, and this is approximately 130 metres south-eastward from where the estimated c 118m summit position was previously given.
The full details for the hill are:
Group: Bro Morgannwg
Name: Wenvoe Quarry
OS 1:50,000 map: 171
Summit Height: 123.4m (LIDAR)
Summit Grid Reference (New Position): ST 13189 74189 (LIDAR)
Bwlch Height: 66m (spot height)
Bwlch Grid Reference: ST 12669 74393 (spot height)
Drop: 57m (LIDAR summit and spot height bwlch)
Dominance: 46.51% (LIDAR summit and spot height bwlch)
Myrddyn Phillips (October 2019)
Cock Hill (ST 153 750) - 23rd summit relocation
Significant Name Changes post for Cock Hill
There has been a Summit Relocation 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 and status of the hill confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Cock Hill (ST 153 750) |
The criteria for the two listings that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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 3rd December 2015.
The name of the hill is Cock Hill and it is adjoined to the Bro Morgannwg group of hills, which are situated in the southern part of South Wales (Region C, Sub-Region C2), and it has the A4232 road to its north and east and a minor road towards its south, and has the city of Caerdydd (Cardiff) towards the north-east.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website this hill was listed with a c 115m summit height positioned at ST 153 750, based on the uppermost ring contour that appears on contemporary Ordnance Survey 1:25,000 Explorer maps which takes in a triangulation pillar with an adjoining flush bracket height of 115.345m positioned at ST 15338 75022.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-evaluated when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online, and as this map gives no further details the summit location remained the same.
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 summit image of Cock Hill |
The summit height produced by LIDAR analysis is 115.6m positioned at ST 15303 75089 with LIDAR also giving a 115.7m height positioned at ST 15310 75062 to a raised field boundary that is excluded from the height of this hill as it is considered a recent man-made construct and with the natural summit of the hill positioned in a different field compared to where the summit was originally listed. The above detail comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct.
Therefore, the summit height produced by LIDAR analysis is 115.6m to ground meeting the criteria used within this list and this is positioned at ST 15303 75089, this is in a different field to the previously listed summit position and is approximately 80 metres north-westward from it and approximately 28 metres from where the highest part of the raised field boundary is situated, and as the latter is considered a relatively recent man-made construct it is not taken as a part of the height of this hill.
The full details for the hill are:
Group: Bro Morgannwg
Name: Cock Hill
OS 1:50,000 map: 171
Summit Height: 115.6m (LIDAR, natural summit)
Summit Grid Reference (new position): ST 15303 75089 (LIDAR, natural summit)
Bwlch Height: 46.3m (LIDAR)
Bwlch Grid Reference: ST 13392 74714 (LIDAR)
Drop: 69.3m (LIDAR)
Dominance: 59.92% (LIDAR)
Myrddyn Phillips (September 2019)
Pt. 103.2m (SS 923 719) - 22nd summit relocation
There has been a Summit Relocation 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 and status of the hill confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR summit image of Pt. 103.2m (SS 923 719) |
The criteria for the two listings that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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 3rd December 2015.
The hill is being listed by the Point (Pt. 103.2m) notation as I do not know an appropriate name for it either from historic research or local enquiry, and it is adjoined to the Bro Morgannwg group of hills, which are situated in the southern part of South Wales (Region C, Sub-Region C2), and it is positioned with the B4265 to its north-east and minor roads to its north and west, and has the small community of Y Wig (Wick) towards the north.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website this hill was listed with a 102m summit height, based on the spot height positioned at SS 921 719 that appears on the Ordnance Survey 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-evaluated when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online, and as this map gives a 103m spot height positioned at SS 92333 71971, the summit of this hill was relocated.
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| Extract from the Ordnance Survey Vector Map Local hosted on the Geograph 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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| Close up LIDAR summit image of Pt. 103.2m (SS 923 719) |
The summit height produced by LIDAR analysis is 103.2m positioned at SS 92366 71993 with LIDAR also giving a 103.4m height positioned at SS 92370 72054 to a raised field boundary that is excluded from the height of this hill as it is considered a recent man-made construct. The above detail comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct.
Therefore, the summit height produced by LIDAR analysis is 103.2m to ground meeting the criteria used within this list and this is positioned at SS 92366 71993, this is relatively close to where the 103m spot height appears on the Ordnance Survey Vector Map Local hosted on the Geograph website and is positioned approximately 170 metres east north-eastward from where the 102m spot height appears on the Ordnance Survey 1:25,000 Explorer map and approximately 60 metres from where the highest part of the raised field boundary is situated, and as the latter is considered a relatively recent man-made construct it is not taken as a part of the height of this hill.
The full details for the hill are:
Group: Bro Morgannwg
Name: Pt. 103.2m
OS 1:50,000 map: 170
Summit Height: 103.2m (LIDAR, natural summit)
Summit Grid Reference (new position): SS 92366 71993 (LIDAR, natural summit)
Bwlch Height: 59.4m (LIDAR)
Bwlch Grid Reference: SS 97154 74620 & SS 97156 74616 & SS 97158 74613 (LIDAR)
Drop: 43.8m (LIDAR)
Dominance: 42.43% (LIDAR)
Myrddyn Phillips (September 2019)
Twyn y Cryn (SO 325 008) - 21st summit relocation
Hill Reclassifications post for Twyn y Cryn
Significant Name Changes post for Twyn y Cryn
There has been confirmation of a Summit Relocation to a hill that is listed in the 100m Twmpau, with the summit height, bwlch height and their locations, the drop and status of the hill confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Twyn y Cryn (SO 325 008) |
The criteria for the list that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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| 100m Twmpau by Myrddyn Phillips |
The name the hill is listed by is Twyn y Cryn, and it is adjoined to the Cefn yr Ystrad group of hills, which are situated in the southern part of South Wales (Region B, Sub-Region B5), and it is positioned with the A4042 road to the west and the A472 road to the north, and has the town of Pont-y-pŵl (Pontypool) towards its west and Brynbuga (Usk) towards its east.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website this hill was listed with twin tops with the prioritised summit positioned at SO 325 005, with an accompanying note stating Two tops of same height – other at SO 326 009.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-evaluated when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online, however both tops were given an uppermost 145m contour ring and no spot height, therefore the details relating to this hill remained the same.
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| Extract from the Ordnance Survey Vector Map Local hosted on the Geograph 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.
%20-%20LIDAR%20summits%201.jpg) |
| LIDAR summit image of Twyn y Cryn (SO 325 008) |
The height produced by LIDAR analysis to the natural summit of this hill is 148.3m positioned at SO 32531 00891, this confirms the summit position and its relocation from its previously prioritised position originally given in the 100m P30 list of Geoff Crowder’s v-g.me website, and as such comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct.
Therefore, the height produced by LIDAR analysis is 148.3m and this is positioned at SO 32531 00891, this position is not given a spot height on contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and is approximately 350 metres northward from where the previously prioritised summit was listed.
The full details for the hill are:
Group: Cefn yr Ystrad
Name: Twyn y Cryn
OS 1:50,000 map: 171
Summit Height: 148.3m (LIDAR)
Summit Grid Reference (New Position): SO 32531 00891 (LIDAR)
Bwlch Height: 113.0m (LIDAR)
Bwlch Grid Reference: SO 32392 01153 (LIDAR)
Drop: 35.3m (LIDAR)
Myrddyn Phillips (September 2019)
The Beech (ST 346 974) - 20th summit relocation
Significant Name Changes post for The Beech
There has been a Summit Relocation 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 and status of the hill confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of The Beech (ST 346 974) |
The criteria for the two listings that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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 3rd December 2015.
The name the hill is now listed by is The Beech and it is adjoined to the Cymoedd Gwent group of hills, which are situated in the eastern part of South Wales (Region C, Sub-Region C2), and it has a number of A roads encircling it with the A4042 to its west, the A472 to its north, the A449 to its east and the M4 motorway towards its south, and has the town of Brynbuga (Usk) towards its north-east.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website this hill was listed with a 184m summit height, based on the spot height positioned at ST 346 974 that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, with the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map positioning this spot height on the south-east side of a field boundary.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
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.
The summit height produced by LIDAR analysis is 185.4m positioned at ST 34645 97459 with LIDAR also giving a 185.5m height positioned at ST 34663 97467 to the raised field boundary that is excluded from the height of this hill as it is considered a recent man-made construct. Importantly the natural summit position of this hill is given by LIDAR to the north-west of the raised field boundary, and as such comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct.
Therefore, the summit height produced by LIDAR analysis is 185.4m to natural ground and this is positioned at ST 34645 97459, and although relatively close to where 184m spot height appears on the Ordnance Survey Vector Map Local hosted on the Geograph website, it is positioned in a different field from where the originally listed summit adjoined to this spot height is placed.
The full details for the hill are:
Group: Cymoedd Gwent
Name: The Beech
OS 1:50,000 map: 171
Summit Height: 185.4m (LIDAR, natural summit)
Summit Grid Reference (new position): ST 34645 97459 (LIDAR, natural summit)
Bwlch Height: 89.0m (LIDAR)
Bwlch Grid Reference: ST 34479 98091 (LIDAR)
Drop: 96.4m (LIDAR)
Dominance: 51.98% (LIDAR)
Myrddyn Phillips (September 2019)
Woodlake Park (ST 343 997) - 19th summit relocation
Significant Name Changes post for Woodlake Park
Significant Height Revisions post for Woodlake Park
There has been confirmation of a Summit Relocation 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 and status of the hill confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Woodlake Park (ST 343 997) |
The criteria for the two listings that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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 3rd December 2015.
The name the hill is listed by is Woodlake Park and it is adjoined to the Cymoedd Gwent group of hills, which are situated in the eastern part of South Wales (Region C, Sub-Region C2), and it is positioned above the Llandegfedd Reservoir which is to its west, and has the town of Pont-y-pŵl (Pontypool) towards its west and Brynbuga (Usk) towards its east.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website this hill was listed with a 147m summit height, based on the spot height positioned at ST 340 994 that appears on the Ordnance Survey 1:50,000 Landranger map, with the 1:25,000 Explorer map having no spot height.
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| Extract from the Ordnance Survey 1:50,000 Landranger map |
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-evaluated when the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map became available online, and as this map gives a 149m spot height positioned at ST 34341 99786, the summit of this hill was relocated.
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| Extract from the Ordnance Survey Vector Map Local hosted on the Geograph 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.
The height produced by LIDAR analysis is 150.7m positioned at ST 34335 99793, this confirms the summit relocation from its position originally given in the 100m P30 list of Geoff Crowder’s v-g.me website, and as such comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct. As heights on different scaled Ordnance Survey maps are not consistent the height given on the 1:25,000 Explorer map is being prioritised in favour of the 1:50,000 Landranger map for detailing these relocations.
Therefore, the height produced by LIDAR analysis is 150.7m and this is positioned at ST 34335 99793, this position is close to where the 149m spot height appears on the Ordnance Survey Vector Map Local hosted on the Geograph website and is approximately 450 metres north north-east from where the originally listed summit adjoined to the 147m spot height is positioned.
The full details for the hill are:
Group: Cymoedd Gwent
Name: Woodlake Park
OS 1:50,000 map: 171
Summit Height: 150.7m (LIDAR)
Summit Grid Reference (new position): ST 34335 99793 (LIDAR)
Bwlch Height: 91.5m (LIDAR)
Bwlch Grid Reference: SO 33405 01033 (LIDAR)
Drop: 59.3m (LIDAR)
Dominance: 39.31% (LIDAR)
Myrddyn Phillips (August 2019)
The Mount (ST 258 848) - 18th summit relocation
Significant Name Changes post for The Mount
Significant Height Revisions post for The Mount
There has been a Summit Relocation to a hill that is listed in the 100m Twmpau and Y Trechol – The Dominant Hills of Wales, with the summit height derived from the OS Trig Database and the bwlch height derived from interpolation of 5m contouring.
The criteria for the two listings that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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 3rd December 2015.
The name of the hill is The Mount and it is adjoined to the Cymoedd Gwent group of hills, which are situated in the eastern part of South Wales (Region C, Sub-Region C2), and it has minor roads to its north-west and north-east and the M4 motorway to its south, and is positioned between the city of Caerdydd (Cardiff) to the south-west and Casnewydd-ar-Wysg (Newport) to the north-east.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website this hill was listed with a 124m summit height, based on the spot height positioned at ST 25276 84738 that appears on the Ordnance Survey 1:25,000 Explorer map, with an accompanying note stating that the Ordnance Survey 1:50,000 Landranger map dated 1986 has a 127m spot height adjoined to a triangulation pillar and which is positioned at ST 25869 84831. As heights on 1:25,000 scale mapping were prioritised in this list over those on 1:50,000 scale mapping this hill’s summit was listed to where the 124m spot height appears on the 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Since publication of these P30 lists on Geoff Crowder’s v-g.me website the heights on different scaled Ordnance Survey maps can be cross referenced against a number of sources that are now available online, and 1:25,000 map data is no longer prioritised for summit heights over that of 1:50,000 map data, each is now assessed individually.
The summit height adjoined to the old triangulation pillar and its position in relation to that previously given comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct. As heights on different scaled Ordnance Survey maps are not consistent the height given on the 1:25,000 Explorer map is being prioritised in favour of the 1:50,000 Landranger map for detailing these relocations.
Therefore, the listed summit height of this hill is 127m and this was derived from the 127.247m flush bracket height adjoined to a triangulation pillar that once stood on the summit of this hill and which was destroyed in September 1985, this position is approximately 550 metres eastward from the previously listed summit position where the 124m spot height appears on the Ordnance Survey 1:25,000 Explorer map.
The full details for the hill are:
Group: Cymoedd Gwent
Name: The Mount
OS 1:50,000 map: 171
Summit Height: 127m
Summit Grid Reference (new position): ST 25868 84839
Bwlch Height: c 66m
Bwlch Grid Reference: ST 24800 87551
Drop: c 61m
Dominance: 48.03%
Myrddyn Phillips (August 2019)
Bryn Bach (SS 903 875) - 17th summit relocation
Hill Reclassifications post for Bryn Bach
Significant Name Changes post for Bryn Bach
Significant Height Revisions post for Bryn Bach
There has been confirmation of a Summit Relocation to a hill that is listed in the 100m Twmpau, with the summit height, bwlch height and their locations, the drop and status of the hill being confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Bryn Bach |
The criteria for the list that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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 name of the hill is Bryn Bach, and this was derived from the Ordnance Survey One-Inch ‘Old Series’ map and it is this name that the hill is now listed by, and it is adjoined to the Cymoedd Morgannwg group of hills, which are situated in the central part of South Wales (Region C, Sub-Region C2), and is positioned with the A4063 road and the Afon Llynfi to its south-west and the A4064 road and the Afon Garw to its south-east, and has the small community of Betws towards the south.
When this hill was originally listed in the 100m height band of Welsh P30 hills on Geoff Crowder’s v-g.me website, its summit was listed at SS900871 and it appeared with an accompanying note stating; Two points of same height – other at SS903875, with these details being taken from the Ordnance Survey 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Prior to LIDAR analysis this hill was listed with an estimated c 31m of drop, based on the 164m summit spot height that appears on the Ordnance Survey Vector Map Local hosted on the Geograph website and which is entitled the Interactive Coverage Map. This spot height appears beside a field boundary at SS 90354 87551.
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| Extract from the Ordnance Survey Vector Map Local hosted on the Geograph 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.
The height produced by LIDAR analysis is 167.0m positioned at SS 90364 87531, and is in a different field and not beside the field boundary compared to the position of the 164m spot height, and confirms this land is higher than the prioritised position originally given in the 100m P30 list of Geoff Crowder’s v-g.me website, and as such comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct. As heights on different scaled Ordnance Survey maps are not consistent the height given on the 1:25,000 Explorer map is being prioritised in favour of the 1:50,000 Landranger map for detailing these relocations.
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| LIDAR summit image of Bryn Bach |
Therefore, the height produced by LIDAR analysis is 167.0m to what is constituted natural ground and this is positioned at SS 90364 87531, this position is not given a spot height on Ordnance Survey maps and is approximately 600 metres north-eastward from where the prioritised listed summit was originally given and is positioned in a different field to where the 164m spot height appears on the Ordnance Survey Vector Map Local hosted on the Geograph website.
The full details for the hill are:
Group: Cymoedd Morgannwg
Name: Bryn Bach
OS 1:50,000 map: 170
Summit Height: 167.0m (LIDAR)
Summit Grid Reference (New Position): SS 90364 87531 (LIDAR)
Bwlch Height: 135.2m (LIDAR)
Bwlch Grid Reference: SS 90511 87849 (LIDAR)
Drop: 31.9m (LIDAR)
Myrddyn Phillips (June 2019)
Mapping Mountains - Summit Relocations - 100m Twmpau
Cae Alen (SH 781 758) - 16th summit relocation
Survey post for Cae Alen
Significant Name Changes post for Cae Alen
There has been a Summit Relocation to a hill that is listed in the 100m Twmpau, with the summit height, its location, the drop and status of the hill confirmed by LIDAR analysis, and a subsequent summit survey with the Trimble GeoXH 6000 conducted by Myrddyn Phillips, with the latter taking place on the 10th October 2018.
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| LIDAR image of Cae Alen and Bwlch Mawr |
The criteria for the list that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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 name of the bounded land where the summit of this hill is situated is Cae Alen and this was derived from the Tithe map, and it is this name that the hill is now listed by. The hill is adjoined to the Carneddau group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the B5106 road to its west and the Afon Conwy (River Conwy) to its east, and has the town of Conwy towards its north.
This summit relocation relates to two points, with the north-easterly point given a 130m summit spot height positioned at SH 781 758 on contemporary Ordnance Survey maps, and the south-westerly point given a small uppermost 130m ring contour positioned at SH 777 755.
When the origin 100m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, the north-easterly 130m map heighted summit positioned at SH 781 758 was prioritised for P30 status over that of the south-westerly point positioned at SH 777 755.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for these hills were re-assessed when the Ordnance Survey Vector Map Local became available online, this map is hosted on the Geograph website and is entitled the Interactive Coverage Map, and as an uppermost contour ring should be prioritised over that of a same map heighted spot height the south-westerly point positioned at SH 777 755 was now prioritised for P30 status over the north-easterly 130m spot heighted summit positioned at SH 781 758.
It was not until LIDAR became available and analysed that the details for these hills 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 Bwlch Mawr |
The height produced by LIDAR analysis and a subsequent survey with the Trimble GeoXH 6000 confirmed the north-easterly summit as higher:
North-easterly summit; Cae Alen: 129.1m at SH 78116 75814
South-westerly summit; Bwlch Mawr: 128.4m at SH 77790 75561
This comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct. As heights on different scaled Ordnance Survey maps are not consistent the height given on the 1:25,000 Explorer map is being prioritised in favour of the 1:50,000 Landranger map for detailing these relocations.
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| The Trimble GeoXH 6000 gathering data at the summit of Cae Alen |
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| The Trimble GeoXH 6000 gathering data at the summit of Bwlch Mawr |
Therefore the height produced by the Trimble GeoXH 6000 survey is 129.1m positioned at SH 78116 758124, this position is given a 130m spot height on contemporary Ordnance Survey maps and is approximately 400m north-east from where the previously listed summit position is situated which was surveyed as being 128.4m in height and positioned at SH 77790 75561.
The full details for the hill are:
Group: Carneddau
Name: Cae Alen
OS 1:50,000 map: 115
Summit Height: 129.1m (converted to OSGM15)
Summit Grid Reference (new position): SH 78116 75814
Bwlch Height: 34.8m (LIDAR)
Bwlch Grid Reference: SH 77629 74003 (LIDAR)
Drop: 94.3m (Trimble summit and LIDAR bwlch)
Myrddyn Phillips (April 2019)
Mapping Mountains - Summit Relocations - 100m Twmpau
Cae Felin Wynt (SS 683 954) - 15th summit relocation
Significant Name Changes post for Cae Felin Wynt
There has been a Summit Relocation to a hill that is listed in the 100m Twmpau and Y Trechol – The Dominant Hills of Wales, with the summit height, its location, the drop and status of the hill being confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Cae Felin Wynt (SS 683 954) |
The criteria for the two lists that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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 3rd December 2015.
The name of the bounded land where the summit of this hill is situated is Cae Felin Wynt and this was derived from the Tithe map, and it is this name that the hill is now listed by. The hill is adjoined to the Fforest Fawr group of hills, which are situated in the western part of South Wales (Region C, Sub-Region C2), and it is positioned with the B5444 and the A4217 roads to its west and the Crymlyn Bog to its east, and has the city of Abertawe (Swansea) towards the west south-west.
When this hill was originally listed in the 100m height band of Welsh P30 hills on Geoff Crowder’s v-g.me website, its summit was listed at SS685956 and it appeared with an accompanying note stating; Two points of same height – other at SS681955.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
Prior to LIDAR analysis this hill was listed with 43m of drop, based on the prioritised 117m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and which is adjoined to a triangulation pillar positioned at SS 68464 95622 and the 74m bwlch spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map.
The second 117m map spot height is positioned at SS 68178 95486 with ground to its east leading to a covered reservoir. The ground at and also close to where each 117m map spot height appears was analysed via LIDAR resulting in the highest natural ground being positioned close to the north-east corner of the covered reservoir, signifying that the natural summit of this hill is now under this man-made construction.
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| LIDAR close up image of the summit of Cae Felin Wynt |
The height produced by LIDAR analysis to the highest natural ground is 118.9m positioned at SS 68320 95490, with LIDAR contouring indicating that the natural summit of this hill is now under the covered reservoir, but as the remaining natural ground beside the covered reservoir is higher than that beside the old listed summit adjacent to the 117m map heighted trig pillar and is at least 100 metres in distance from it this comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct. As heights on different scaled Ordnance Survey maps are not consistent the height given on the 1:25,000 Explorer map is being prioritised in favour of the 1:50,000 Landranger map for detailing these relocations.
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| The Ordnance Survey's Vector Map Local hosted on the Geograph website with the highest natural ground circled |
Therefore the height produced by LIDAR analysis is 118.9m to natural ground and this is positioned at SS 68320 95490, this position is not given a spot height on Ordnance Survey maps and is approximately 200 metres south-westward from where the previously listed summit position is situated beside the 117m map heighted trig pillar that appears on contemporary Ordnance Survey maps.
The full details for the hill are:
Group: Fforest Fawr
Name: Cae Felin Wynt
OS 1:50,000 map: 159
Summit Height: 118.9m (LIDAR, natural ground)
Summit Grid Reference: SS 68320 95490 (LIDAR, natural ground)
Bwlch Height: 74.2m (LIDAR)
Bwlch Grid Reference: SS 67837 95105 (LIDAR)
Drop: 44.7m (LIDAR)
Dominance: 37.57% (LIDAR)
Myrddyn Phillips (April 2019)
Mapping Mountains - Summit Relocations - 100m Twmpau
Dinas Dinorwig (SH 549 652) - 14th summit relocation
Survey post for Dinas Dinorwig
Significant Name Changes post for Dinas Dinorwig
There has been a Summit Relocation to a hill that is listed in the 100m Twmpau, with the summit height and its location, and the drop of the hill being confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| Dinas Dinorwig (SH 549 652) |
The criteria for the list that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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 name of the hill is Dinas Dinorwig and it is adjoined to the Glyderau group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is encircled by an old track to its north and minor roads to its west, south and east, with the B4366 to its north-west and the A4244 to its north-east, and has the small communities of Bethel towards the west, Rhiwlas towards the east and Llanrug towards the south-west.
Prior to LIDAR analysis this hill was listed with 38m of drop based on its 170m summit spot height positioned at SH 54966 65306 that appears on the Ordnance Survey 1:25,000 Explorer map (with the 1:50,000 Landranger map giving a 169m summit spot height) and a bwlch height of 132m based on the spot height that appears on the Ordnance Survey 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The upper part of this hill comprises an ancient Iron Age Hillfort that has a series of steep embankments and ditches which are in the main overgrown with brambles, bracken and small trees, whilst the inner central part used to be grazed and is now a paddock with an extremely friendly horse when I last visited. It is this inner central part of the summit area where the 170m spot height is positioned.
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| LIDAR image of Dinas Dinorwig |
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 summit image of Dinas Dinorwig |
The summit height produced by LIDAR analysis is 169.6m and is positioned at SH 54955 65254, this position is to the highest part of the ancient embankments, whereas the height produced by LIDAR analysis to the high point of the inner central part of the hill is 169.0m and is positioned at SH 54964 65302, this latter point was surveyed with the Trimble GeoXH 6000 as being 169.2m in height. As the location of this hill’s listed summit is to a different feature compared to its previously listed summit this comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the listed summit is relocated to a different feature compared to its previous listed position, or when the summit of the hill is in a different field compared to where previously given, or when the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct. As heights on different scaled Ordnance Survey maps are not consistent the height given on the 1:25,000 Explorer map is being prioritised in favour of the 1:50,000 Landranger map for detailing these relocations.
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| The Trimble set-up position with the very friendly horse at the old listed summit position of Dinas Dinorwig |
Therefore the height produced by LIDAR analysis is 169.6m and this is positioned at SH 54955 65254, this position is approximately 50 metres south from where the 170m spot height appears on Ordnance Survey 1:25,000 Explorer maps and which was surveyed as being 169.2m in height, and importantly the new summit position is to a different feature.
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| The summit of Dinas Dinorwig |
The full details for the hill are:
Group: Glyderau
Name: Dinas Dinorwig
OS 1:50,000 map: 114, 115
Summit Height: 169.6m (LIDAR)
Summit Grid Reference (new position): SH 54955 65254 (LIDAR)
Bwlch Height: 131.8m (LIDAR)
Bwlch Grid Reference: SH 54648 64645 (LIDAR)
Drop: 37.8m (LIDAR)
Pt. 118.9m (SN 710 294) - 13th summit relocation
There has been a Summit Relocation to a hill that is listed in the 100m Twmpau and the 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.
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| LIDAR image of Pt. 118.9m (SN 710 294) |
The criteria for the two lists that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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| 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 3rd December 2015, and the list is now available inits entirety on Mapping Mountains in Google Doc format.
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| Y Trechol - The Dominant Hills of Wales by Myrddyn Phillips |
The hill is being listed by the point (Pt. 118.9m) notation and it is adjoined to the Mynydd Du group of hills, which are situated in the southern part of South Wales (Region B, Sub-Region B5), and it is positioned with the Afon Tywi (River Towy) and the A40 road to its west, the B4069 road to its east, and has the village of Llangadog towards the south.
When the original 100m height band of Welsh P30hills were published on Geoff Crowder’s v-g.me website, this hill was included in the main P30 category and listed with a 119m summit height based on the spot height positioned at SN 72465 30422 and which appears on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
After the sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-assessed and it was listed with an estimated c 50m of drop and 42.02% dominance, based on the 119m summit spot height an estimated c 69m bwlch height, based on interpolation of 5m contouring between 65m - 70m that appeared on 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.
LIDAR analysis gives the highest ground on this hill as 119.8m positioned at SN 71062 29399. However, this is a part of a raised field boundary and protocols dictate that as this is deemed a relatively recent man-made construct such ground is discounted from the height of a hill.
%20-%20LIDAR%20summit%202.jpg) |
| LIDAR summit image of Pt. 118.9m (SN 710 294) |
The height produced by LIDAR analysis to the natural ground of this hill is 118.0m and is positioned at SN 71046 29411, and this comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies when the high point of the hill is found to be positioned; in a different field, to a different feature such as in a conifer plantation, within a different map contour, to a different point where a number of potential summit positions are within close proximity, when natural ground or the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary or covered reservoir that is judged to be a relatively recent man-made construct, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist.
Therefore, the height produced by LIDAR analysis to the natural summit of this hill is 118.9m and is positioned at SN 71046 29411, this position is clost to where the 119m spot height appears on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, and is approximately 18 metres north-westward from where the high point of the raised field boundary is positioned.
The full details for the hill are:
Group: Mynydd Du
Name: Pt. 118.9m
OS 1:50,000 map: 146, 160
Summit Height: 118.9m (LIDAR)
Summit Grid Reference: SN 71046 29411 (LIDAR)
Bwlch Height: 69.9m (LIDAR)
Bwlch Grid Reference: SN 72466 30393 (LIDAR)
Drop: 48.9m (LIDAR)
Dominance: 41.16% (LIDAR)
Myrddyn Phillips (February 2019)
Cae Ddu Main (SN 622 983) - 12th summit relocation
Significant Name Changes post for Cae Ddu Main
There has been a Summit Relocation to a hill that is listed in the 100m Twmpau and also now in Y Trechol – The Dominant Hills of Wales, with the summit height, its location, the drop and status of the hill confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Cae Ddu Main |
The criteria for the two lists that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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 3rd December 2015.
The name of the bounded land where the summit of this hill is situated is Cae Ddu Main and this was derived from the Tithe map, and it is this name that the hill is now listed by. The hill is adjoined to the Mynydd Penlle’rcastell group of hills, which are situated in the western part of South Wales (Region C, Sub-Region C1), and is positioned with the A483 road to its immediate west and the A48 and M4 to its north, and has the village of Penlle’r-gaer to its north.
If wanting to visit the hill permission to do so should be sought as the summit area is not a part of designated open access land, for those wishing to do so an approach from the north may be feasible.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website the summit location of this hill was given to the 102m spot height that is positioned at SS 619 984 on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps. However, the 1:25,000 Explorer map has a small uppermost 105m ring contour to the east of the 102m spot height.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The summit relocation to land within the 105m ring contour has now been confirmed by LIDAR analysis and this land is confirmed as higher than that at the 102m spot height to its west.
The summit height produced by LIDAR analysis is 106.9m to remaining natural ground, and its position in relation to that originally given comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct. As heights on different scaled Ordnance Survey maps are not consistent the height given on the 1:25,000 Explorer map is being prioritised in favour of the 1:50,000 Landranger map for detailing these relocations.
The summit height produced by LIDAR analysis is 106.9m to remaining natural ground and is positioned at SS 62212 98337, this position is approximately 290 metres east from where the summit was originally listed at the position of the 102m spot height.
The full details for the hill are:
Group: Mynydd Penlle’rcastell
Name: Cae Ddu Main
OS 1:50,000 map: 159
Summit Height: 106.9m (LIDAR, remaining natural high point)
Summit Grid Reference (new position): SN 62212 98337 (LIDAR, remaining natural high point)
Bwlch Height: 69.1m (LIDAR, natural bwlch)
Bwlch Grid Reference: SN 62051 00000 (LIDAR, natural bwlch)
Drop: 37.8m (LIDAR)
Dominance: 35.34% (LIDAR)
Myrddyn Phillips (February 2019)
Mapping Mountains - Summit Relocations - 100m Twmpau
Bryniau (SH 579 711) - 11th summit relocation
Survey post for Bryniau
Significant Name Changes post for Bryniau
Hill Reclassifications post for Bryniau
There has been a Summit Relocation to a hill that is listed in the 100m Twmpau, with the summit height and its location, drop and status of the hill initially confirmed by LIDAR analysis and subsequently by a summit survey with the Trimble GeoXH 6000 which were conducted by Myrddyn Phillips, with the latter taking place on the 1st October 2018.
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| Bryniau (SH 579 711) |
The criteria for the list that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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 land where the summit of this hill is situated is a part of Bryniau and this was derived from local enquiry and substantiated from the Tithe map, and it is the name that this hill is now listed by. The hill is adjoined to the Glyderau group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and is positioned with the A4087 road to its west and minor roads to its south and east, and has the small city of Bangor towards its north.
If wanting to visit the hill permission to do so should be sought as the summit area is not a part of designated open access land, for those wishing to do so the easiest approach is via a track leading to the old farmhouse of Bryniau.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website the summit location of this hill was given to the 117m spot height adjoined to a triangulation pillar that appeared on contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps and which is positioned at SH 578 711.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-examined when the Ordnance Survey Interactive Coverage Map hosted on the Geograph website became available online and this map gives a 118m spot height positioned to the north-east of the trig pillar at SH 579 711.
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| Extract from the Ordnance Survey Interactive Coverage Map hosted on the Geograph website |
However, it was not until LIDAR became available that these two positions could be compared and confirmation that the land where the 118m spot height appears is higher than the land beside the 117 map heighted trig pillar.
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| LIDAR image of Bryniau |
The summit height produced by the Trimble GeoXH 6000 survey is 117.6m, and its position in relation to that originally given comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct. As heights on different scaled Ordnance Survey maps are not consistent the height given on the 1:25,000 Explorer map is being prioritised in favour of the 1:50,000 Landranger map for detailing these relocations.
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| The Trimble GeoXH 6000 gathering data at the summit of Bryniau |
The summit height produced by the Trimble GeoXH 6000 is 117.6m and is positioned at SH 57971 71196, this position is approximately 80 metres north-east from where the summit was originally listed at this hill’s triangulation pillar.
The full details for the hill are:
Group: Glyderau
Name: Bryniau
OS 1:50,000 map: 114, 115
Summit Height: 117.6m (converted to OSGM15)
Summit Grid Reference (new position): SH 57971 71196
Bwlch Height: 87.4m (LIDAR)
Bwlch Grid Reference: SH 57748 70845 (LIDAR)
Drop: 30.1m (Trimble summit and LIDAR bwlch)
Myrddyn Phillips (February 2019)
Mapping Mountains - Summit Relocations - 100m Twmpau
Parc Llwyn Du (SN 428 188) - 10th summit relocation
Survey post for Parc Llwyn Du
Significant Name Changes post for Parc Llwyn Du
There has been a Summit Relocation to a hill that is listed in the 100m Twmpau, with the summit height and its location, drop and status of the hill initially confirmed by LIDAR analysis and subsequently by a summit survey with the Trimble GeoXH 6000 which were conducted by Myrddyn Phillips, with latter taking place on the 31st July 2018.
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| Parc Llwyn Du (SN 428 188) |
The criteria for the list that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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 name of the bounded land where the summit of this hill is situated is Parc Llwyn Du and this was derived from the Tithe map, and it is the name that this hill is now listed by. The hill is adjoined to the Mynydd Sylen group of hills, which are situated in the western part of South Wales (Region C, Sub-Region C1), and is positioned with the A 48 road to its south and the B 4300 road to its north, and has the town of Caerfyrddin (Carmarthen) to the north-west.
If wanting to visit the hill permission to do so should be sought as the summit area is not a part of designated open access land, for those wishing to do so the nearest public footpath is to the south of the summit.
When the original Welsh 100m P30 list was published on Geoff Crowder’s v-g.me website the summit location of this hill was given to the 104m spot height adjoined to a triangulation pillar that appeared on contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps and positioned at SN 423 186. However, this trig pillar is placed on a covered reservoir that is considered a recent man-made construct and therefore not a part of the natural summit of the hill.
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| Extract from the Ordnance Survey 1:25,000 Explorer map |
The details for this hill were re-examined when the Ordnance Survey Interactive Coverage Map hosted on the Geograph website became available online and this map also gave a 104m spot height positioned at SN 428 188, and which is placed on natural ground. However, it was not until LIDAR became available that an accurate height comparison could be made between these two positions.
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| Extract from the Ordnance Survey Interactive Coverage Map hosted on the Geograph website |
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| LIDAR image of Parc Llwyn Du |
The summit height produced by DTM LIDAR analysis is 104.1m at SN 42895 18829, with the summit subsequently surveyed using the Trimble GeoXH 6000 resulting in a 104.3m summit height positioned at SN 42895 18827, and its position in relation to that originally given comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct. As heights on different scaled Ordnance Survey maps are not consistent the height given on the 1:25,000 Explorer map is being prioritised in favour of the 1:50,000 Landranger map for detailing these relocations.
The summit height produced by the Trimble GeoXH 6000 is 104.3m and is positioned at SN 42895 18827, this position is approximately 30 metres east from where the 104m spot height appears on the Ordnance Survey Interactive Coverage Map hosted on the Geograph website, and over 560 metres east north-eastward from where the summit was originally listed at this hill’s triangulation pillar.
The full details for the hill are:
Group: Mynydd Sylen
Name: Parc Llwyn Du
OS 1:50,000 map: 159
Summit Height: 104.3m (converted to OSGM15, natural summit)
Summit Grid Reference (new position): SN 42895 18827
Bwlch Height: 73.4m (LIDAR)
Bwlch Grid Reference: SN 43247 18917 (LIDAR)
Drop: 30.8m (Trimble summit and LIDAR bwlch)
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| The Trimble set-up position at the summit of Parc Llwyn Du |
Myrddyn Phillips (January 2019)
Mapping Mountains - Summit Relocations - 100m Twmpau
Cae Uchaf (SS 575 943) - 9th summit relocation
Significant Name Changes post for Cae Uchaf
There has been a Summit Relocation to a hill that is listed in the 100m Twmpau and Y Trechol – The Dominant Hills of Wales, with the summit height, drop and status of the hill being confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR summit image of Cae Uchaf |
The criteria for the two lists that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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 addition Welsh P30 hills whose prominence is 33.33% or more and below 50% 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 3rd December 2015.
The name of the bounded land where the summit of this hill is situated is Cae Uchaf and this was derived from the Tithe map, and it is the name that this hill is now listed by. The hill 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 with the B 4296 road to its east, and has the small community of Y Crwys (Three Crosses) at its base to the west south-west.
If wanting to visit the hill permission to do so should be sought as the summit area is not a part of designated open access land, for those wishing to do so the nearest public footpath is to the north of the summit.
Prior to LIDAR analysis this hill was listed with 70m of drop and 48.61% dominance based on the 144m summit spot height and 74m bwlch spot height that appear on the Ordnance Survey 1:25,000 Explorer map.
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| LIDAR bwlch image of Cae Uchaf showing the natural bwlch to be intact |
The summit height produced by 1m DTM LIDAR analysis is 144.4m at SS 57511 94397 and its position in relation to that previously given comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct. As heights on different scaled Ordnance Survey maps are not consistent the height given on the 1:25,000 Explorer map is being prioritised in favour of the 1:50,000 Landranger map for detailing these relocations.
The summit height produced by 1m DTM LIDAR analysis is 144.4m and is positioned at SS 57511 94397, this position is not given a spot height on contemporary Ordnance Survey maps and is approximately 65 metres west and in a different field from where the 144m spot height appears on the Ordnance Survey 1:25,000 Explorer map.
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| Ordnance Survey Interactive Coverage Map hosted on the Geograph website showing the summit position in relation to where the 144m spot height appears |
The full details for the hill are:
Group: Gŵyr
Name: Cae Uchaf
OS 1:50,000 map: 159
Summit Height: 144.4m (LIDAR)
Summit Grid Reference (new position): SS 57511 94397 (LIDAR)
Bwlch Height: 73.4m (LIDAR, natural bwlch remains)
Bwlch Grid Reference: SS 50983 90868 (LIDAR)
Drop: 71.0m (LIDAR)
Dominance: 49.19% (LIDAR)
Myrddyn Phillips (November 2018)
Mapping Mountains - Summit Relocations - 100m Twmpau
Five Acres (SS 537 932) - 8th summit relocation
Significant Name Changes post for Five Acres
There has been a Summit Relocation to a hill that is listed in the 100m Twmpau, with the summit height, drop and status of the hill being confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Five Acres |
The criteria for the list that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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 name of the bounded land where the natural summit of this hill is situated is Five Acres and this was derived from the Tithe map, and it is the name that this hill is now listed by. The hill 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 between the B roads of the 4295 to the north-west and 4271 to the south, and has the village of Pen-clawdd towards the north.
If wanting to visit the hill permission to do so should be sought as the summit area is not a part of designated open access land, for those wishing to do so the nearest public footpath is to its south, with other possibilities via gated fields to the east.
Prior to LIDAR analysis this hill was listed with an estimated c 43m drop, with an estimated c 127m summit height based on an uppermost 125m ring contour and an estimated c 84m bwlch height based on interpolation of 5m contouring between 80m – 85m on the Ordnance Survey 1:25,000 Explorer map.
The summit height produced by 1m DTM LIDAR analysis is 125.1m (125.059m) and this height is given to four separate points, these are positioned at SS 53779 93281 and SS 53779 93291 and SS 53774 93296 and SS 53780 93297. LIDAR contouring indicates that these positions are a part of the existing natural summit of the hill, whilst also indicating that a higher point exists; 125.2m (125.190m) at SO 53791 93318 which is a part of a raised field boundary which is considered a relatively recent man-made construct, therefore it is the position of the natural summit that is being listed for this hill. As the raised field boundary is higher than the natural summit of the hill this comes within the parameters of the Summit Relocations used within this page heading, these parameters are:
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| The position of the natural summit of Five Acres |
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| The position of the high point of the raised field boundary |
The term Summit Relocations applies to any listed hill whose summit meets the following criteria; where there are a number of potential summit positions within close proximity and the highest point is not where previously given, or a relocation of approximately 100 metres or more in distance from either the position of a map spot height or from where the summit of the hill was previously thought to exist, or when the summit of the hill is in a different field compared to where previously given, or when the natural and intact summit of a hill is confirmed compared to a higher point such as a raised field boundary that is judged to be a relatively recent man-made construct. As heights on different scaled Ordnance Survey maps are not consistent the height given on the 1:25,000 Explorer map is being prioritised in favour of the 1:50,000 Landranger map for detailing these relocations.
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| LIDAR image of the summit area of Five Acres with the field boundary's being distinctly shown |
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| Close-up LIDAR image of the summit of Five Acres |
The summit height produced by 1m DTM LIDAR analysis is 125.1m (125.059m) and this height is given to four separate points, these are positioned at SS 53779 93281 and SS 53779 93291 and SS 53774 93296 and SS 53780 93297. These positions are a part of the natural summit of the hill and not given a spot height on Ordnance Survey maps, they are approximately 40 metres from the raised field boundary that LIDAR gives as higher, but this point is considered a relatively recent man-made construct.
The full details for the hill are:
Group: Gŵyr
Name: Five Acres
OS 1:50,000 map: 159
Summit Height: 125.1m (LIDAR)
Summit Grid Reference: SS 53779 93281 and SS 53779 93291 and SS 53774 93296 and SS 53780 93297 (LIDAR, natural summit) (LIDAR gives a 125.2m high raised field boundary positioned at SS 53791 93318 which is considered a relatively recent man-made construct)
Bwlch Height: 84.3m (LIDAR)
Bwlch Grid Reference: SS 56307 93757 (LIDAR)
Drop: 40.8m (LIDAR)
Mapping Mountains - Summit Relocations - 100m Twmpau
Allt Cunedda (SN 407 090) - 7th summit relocation
There has been a Summit Relocation to a hill that is listed in the 100m Twmpau and Y Trechol – The Dominant Hills of Wales, with the summit height and position confirmed by LIDAR analysis conducted by Myrddyn Phillips.
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| LIDAR image of Allt Cunedda with the raised covered reservoir on bottom left and the summit of Allt Cunedda in the centre right |
The criteria for the two listings that this summit relocation applies to are:
100m Twmpau - Welsh hills at or above 100m and below 200m in height with 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.
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 addition Welsh P30 hills whose prominence is 33.3% or more and below 50% of their absolute height, with the Introduction to the Mapping Mountains publication of this list appearing on the 3rd December 2015.
The name of the hill is Allt Cunedda and it is adjoined to the Mynydd Sylen group of hills, which are situated in the western part of South Wales (Region C, Sub-Region C1), and is positioned with the stream valley of the Gwendraeth Fach and the A 484 road to the east, and has the small town of Cydweli (Kidwelly) towards the south.
As the summit of this hill is not a part of designated open access land permission to visit should be sought, for those wishing to do so the nearest public footpath is to the south of the summit and relatively close to it.
Prior to LIDAR analysis this hill was listed with c 129m of drop based on the 192m summit spot height that is given to a triangulation pillar on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps and an estimated bwlch height of c 63m based on interpolation of bwlch contouring between 60m – 65m.
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| Extract from the Ordnance Survey Interactive Coverage Map hosted on the Geograph website showing the summit position in relation to the trig pillar spot height position |
The triangulation pillar is given a flush bracket height of 192.353m and is positioned at SN 40676 08999 and sits atop a concrete plinth that is approximately 0.15 – 0.2m high, and is positioned on grass at the base of a covered reservoir beside a concrete track giving access from a gate. The trig pillar seems to have been positioned on the hill before the construction of the covered reservoir and therefore in all likelihood is placed on natural ground. Therefore, dependent upon the accuracy of the flush bracket, the ground at the base of the trig pillar is approximately 191.8 - 191.9m in height.
The summit height produced by 1m DTM LIDAR analysis is 192.7m and is positioned at SN 40749 09013, this position is to the remains of a barrow that has been ploughed down to approximately 0.5m in height and which is situated in a field. This position is not given a spot height on Ordnance Survey maps and is approximately 75 metres east from where the previously listed summit position is situated.
The full details for the hill are:
Group: Mynydd Sylen
Name: Allt Cunedda
Summit Height: 192.7m (LIDAR)
OS 1:50,000 map: 159
Summit Grid Reference (New Position): SN 40749 09013 (LIDAR)
Drop: c 130m
Dominance: 67.30% (LIDAR)
Mapping Mountains - Summit Relocations - 100m Twmpau
Pt. 173.8m (SN 225 503) - 6th summit relocation
Survey post for Pt. 173.8m
There has been a Summit Relocation to the 100m Twmpau (thirty welsh metre prominences and upward) list initiated by a survey with the Trimble GeoXH 6000, with the survey that resulted in this summit relocation being conducted on the 13th May 2016.
The hill is adjoined to the Rhos Ymryson range of hills and is situated to the north-east of Aberteifi (Cardigan) and to the west south-west of Aberporth, with the high point of the hill being close to the small community of Felinwynt which only comprises a few houses, and as the hill does not possess a name of its own on current Ordnance Survey maps, and as I do not know an appropriate name for it either from local enquiry or from historical research it is being listed under the point (Pt. 173.8m) notation.
Access to the hill is relatively easy as it comprises a large grassy field which has a minor lane running over it in a north to south direction. However, the high point as surveyed with the Trimble GeoXH 6000 is not on open access land and therefore permission to visit should be sought.
The highest spot height adjoined to this hill on Ordnance Survey maps is 174m and this is positioned on the minor lane and adjacent to where a fence heads westward across a field. A data set was taken with the Trimble from the high point of the road as well as from what was deemed to be the high point of the adjacent field, the results appear below:
High point of road: 173.7m (173.695m, converted to OSGM15)
High point of field: 173.8m (173.811m, converted to OSGM15)
These two results are very close and there is a possibility that higher ground exists in the field when compared to where the Trimble set-up position was placed. However, for now this Trimble data is the most accurate that is known for this hill, and although the corner of the field is very close to the high point of the road it is worth itemising this positional change as a summit relocation as many people may just dip their toe on the tarmac instead of visiting the land within the adjacent field.
Therefore, the known higher part of the hill as surveyed with the Trimble GeoXH 6000 is not on the minor lane as ground in the adjacent westerly field is approximately 0.12m higher.
The full details for the hill are:
Cardinal Hill: Rhos Ymryson
Summit Height: 173.8m (converted to OSGM15)
Name: Pt. 173.8m
OS 1:50,000 map: 145
Summit Grid Reference (New Position): SN 22587 50306
Drop: c 55m
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| The Trimble GeoXH 6000 gathering data at the summit of Pt. 173.8m, with the minor road where the 174m spot height appears on the ground on the other side of the gorse hedgerow in the background of this photograph |
For details on the survey that relocated the summit of this hill.
Myrddyn Phillips (May 2016)
Mapping Mountains - Summit Relocations - 100m Twmpau
Pentre Clawdd Gorse (SJ 311 442) - 5th summit relocation
Summit survey post for Pentre Clawdd Gorse
Bwlch survey post for Pentre Clawdd Gorse
Hill Reclassifications post for Pentre Clawdd Gorse
There has been a Summit Relocation to a hill is now listed in the 100m Twmpau (thirty welsh metre prominences and upward) due to a survey with the Trimble GeoXH 6000 conducted by Myrddyn Phillips and which took place on the 23rd February 2016.
The name of the hill is Pentre Clawdd Gorse and it is positioned in the eastern part of the Moel y Gamelin range of hills, and situated to the east of the A 483 and north-east of the town of Rhiwabon (Ruabon). Access to the hill is relatively easy as its summit is positioned on Wat’s Dyke, this ancient earthwork stretches from the Dee estuary in the north to Shropshire in the south, and public footpaths follow its course over this hill’s broad north – south summit ridge.
The name of the hill is Pentre Clawdd Gorse and it is positioned in the eastern part of the Moel y Gamelin range of hills, and situated to the east of the A 483 and north-east of the town of Rhiwabon (Ruabon). Access to the hill is relatively easy as its summit is positioned on Wat’s Dyke, this ancient earthwork stretches from the Dee estuary in the north to Shropshire in the south, and public footpaths follow its course over this hill’s broad north – south summit ridge.
Pentre Clawdd Gorse is adjoined to the summit of Wynnstay Park (SJ 31001 42958) which is approximately one kilometre due south from it, with the latter having a 141m spot height given it on Ordnance Survey 1:25,000 Explorer maps. The summit of Wynnstay Park was surveyed on the 20th October 2015 with the Trimble GeoXH 6000 and subsequently analysed via LIDAR, resulting in a 141.2m summit height.
As the summit of Pentre Clawdd Gorse was surveyed as 0.8m higher than Wynnstay Park, and as the latter was listed in the Hills to be surveyed sub list that accompanied the original Welsh 100m P30 listings on Geoff Crowder’s v-g.me website, and as the height of the bwlch between these two hills in only 128.2m, the summit of the qualifying hill has been relocated to that of Pentre Clawdd Gorse.
Therefore, the position of the relocated summit is at SJ 31131 44252 and is situated on the highest point of this part of the ancient earthwork known as Wat’s Dyke. Either side of this earthwork are fields, one given over to grazing and the other which is arable. This part of Wat’s Dyke has a narrow line of mature trees growing on it which adds perspective and interest to the landscape, although their proximity hampered satellite reception. This position is not given a spot height on contemporary Ordnance Survey maps and has an uppermost contour ring of 140m, and is approximately 1.4 kilometres northward of the summit of Wynnstay Park.
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| LIDAR image of Pentre Clawdd Gorse (SJ 311 442) |
As the summit of Pentre Clawdd Gorse was surveyed as 0.8m higher than Wynnstay Park, and as the latter was listed in the Hills to be surveyed sub list that accompanied the original Welsh 100m P30 listings on Geoff Crowder’s v-g.me website, and as the height of the bwlch between these two hills in only 128.2m, the summit of the qualifying hill has been relocated to that of Pentre Clawdd Gorse.
Therefore, the position of the relocated summit is at SJ 31131 44252 and is situated on the highest point of this part of the ancient earthwork known as Wat’s Dyke. Either side of this earthwork are fields, one given over to grazing and the other which is arable. This part of Wat’s Dyke has a narrow line of mature trees growing on it which adds perspective and interest to the landscape, although their proximity hampered satellite reception. This position is not given a spot height on contemporary Ordnance Survey maps and has an uppermost contour ring of 140m, and is approximately 1.4 kilometres northward of the summit of Wynnstay Park.
The full details for the hill are:
Group: Moel y Gamelin
Name: Pentre Clawdd Gorse
OS 1:50,000 map: 117
Summit Height: 142.0m (converted to OSGM15)
OS 1:50,000 map: 117
Summit Height: 142.0m (converted to OSGM15)
Summit Grid Reference (New Position): SJ 31131 44252
Bwlch Height: 109.8m (LIDAR)
Bwlch Grid Reference: SJ 30789 44141 (LIDAR)
Drop: 32.2m (Trimble summit and LIDAR bwlch)
Bwlch Grid Reference: SJ 30789 44141 (LIDAR)
Drop: 32.2m (Trimble summit and LIDAR bwlch)
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| The Trimble GeoXH 6000 gathering data at the summit of Pentre Clawdd Gorse, with the summit of Wynnstay Park on the left and in the background of this photograph |
For details on the survey that relocated the summit of this hill please click {here}
Myrddyn Phillips (February 2016)
Wynnstay Park (SJ 309 429) - 4th summit relocation
Survey post for Wynnstay Park
There has been a Summit Relocation to a hill that was originally surveyed for 100m Twmpau (thirty welsh metre prominences and upward) status, and which was initiated by a survey with the Trimble GeoXH 6000 and confirmed by subsequent LIDAR analysis, with these details retrospective as the survey that resulted in this summit relocation was conducted on the 20th October 2015.
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| LIDAR image of Wynnstay Park (SJ 309 429) |
The survey was conducted in the eastern part of the Moel y Gamelin range of hills, on the south-eastern outskirts of Rhiwabon (Ruabon), with the hill being situated on the old country estate of the Wynn family; the estate house has now been converted to flats and private houses. Access to the hill is easy from the north as a paved road leads to its summit. Parking can either be found adjacent to Broth Lodge at the entrance to the old estate or if wanting a quick visit a car can be driven up the road and parked within 100 metres of the high point of the hill.
The name of the hill is Wynnstay Park and prior to the survey with the Trimble GeoXH 6000 the summit position was listed as SJ 310 430, this is where the 141m spot height appears on the Ordnance Survey 1:25,000 Explorer map. However, the Trimble set-up position was south south-westward from where the spot height appears on the ground, and with LIDAR giving the summit position as SJ 31001 42958.
Therefore, the position of the summit is at SJ 31001 42958 and is beside a fence next to the road that makes its way toward the old estate house. This position is not given a spot height on contemporary Ordnance Survey maps although it is close to where the 141m spot height appears.
The full details for the hill are:
Therefore, the position of the summit is at SJ 31001 42958 and is beside a fence next to the road that makes its way toward the old estate house. This position is not given a spot height on contemporary Ordnance Survey maps although it is close to where the 141m spot height appears.
The full details for the hill are:
Group: Moel y Gamelin
Name: Wynnstay Park
OS 1:50,000 map: 117
Summit Height: 141.2m (LIDAR)
OS 1:50,000 map: 117
Summit Height: 141.2m (LIDAR)
Summit Grid Reference (New Position): SJ 31001 42958 (LIDAR)
Bwlch Height: 128.2m (LIDAR)
Bwlch Grid Reference: SJ 31418 43293 (LIDAR
Drop: 13.0m (LIDAR)
Bwlch Grid Reference: SJ 31418 43293 (LIDAR
Drop: 13.0m (LIDAR)
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| The summit area of Wynnstay Park |
Myrddyn Phillips (October 2015)
Mapping Mountains - Summit Relocations - 100m Twmpau
The Pimple (SJ 299 472) - 3rd summit relocation
Survey post for The Pimple
Hill Reclassifications post for The Pimple
Significant Height Revisions post for The Pimple
Significant Name Changes post for The Pimple
There has been a Summit Relocation to the list of the 100m Twmpau (thirty welsh metre prominences and upward) initiated by a survey with the Trimble GeoXH 6000, with the following details being retrospective as the survey that resulted in this summit relocation was conducted on the 20th October 2015.
Accompanying the main P30 list is a sub list entitled the 100m Sub-Twmpau that takes in all Welsh hills at or over 100m and below 200m in height that have 20m or more and below 30m of drop. It is this sub category that this hill in now included in, as prior to the survey with the Trimble GeoXH 6000 it had not been listed in the sub list adjoined to the original P30 lists on Geoff Crowder’s v-g.me website.
The survey was conducted in the eastern part of the Bryniau Clwyd range of hills, above the small community of Pentre Bychan which is adjacent to the larger community of Rhosllanerchrugog, and the hill can be accessed from its west where a public footpath traverses the course of the valley where its bwlch is positioned. However, permission should be sought for those wishing to visit as the summit is not on open access land. When I visited I asked permission to do so and was kindly directed to the best ascent route.
The survey was conducted in the eastern part of the Bryniau Clwyd range of hills, above the small community of Pentre Bychan which is adjacent to the larger community of Rhosllanerchrugog, and the hill can be accessed from its west where a public footpath traverses the course of the valley where its bwlch is positioned. However, permission should be sought for those wishing to visit as the summit is not on open access land. When I visited I asked permission to do so and was kindly directed to the best ascent route.
The name of the hill is The Pimple; this is a locally known name that was given me when I made enquiries during the survey for its bwlch position. The hill remains unnamed on current Ordnance Survey maps and its locally known name relates directly to the past industrial heritage of the hill, as its summit is made of mining waste that is now stabilised and grassed over. The uppermost part of the summit is relatively small in area and squat in shape, and hence its name, as it resembles a pimple as it sits upon another elevated part of the hill.
Although prior to the survey with the Trimble GeoXH 6000 the hill was not classified, its summit position was indicated to be at SJ 30075 47320, this is where a 154m spot height appears on current Ordnance Survey maps. This spot height is positioned in a field which when I visited, had been ploughed and probably seeded. However there is also high ground to the south-west of where the 154m spot height appears on the ground and each respective high point was surveyed, with the following results:
South-western high point (The Pimple): 153.5m (converted to OSGM15) at SJ 29984 47262
North-eastern high point (154m spot height in field): 153.1m (converted to OSGM15) at SJ 30071 47279
Therefore the position of the relocated summit is at SJ 29984 47262 and is the top of a relatively small and squat mound made of old mining spoil that is now stabilised and grassed over. This position is not given a spot height on current Ordnance Survey maps but the Trimble result gave it as 0.4m higher when compared to the position where the 154m spot height appears on the ground and approximately 115 metres south-westward from it.
The full details for the hill are:
Cardinal Hill: Moel y Gamelin
Summit Height: 153.5m (converted to OSGM15)
Name: The Pimple
OS 1:50,000 map: 117
Summit Grid Reference (New Position): SJ 29984 47262
Drop: 25.2m (converted to OSGM15)
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| The Trimble GeoXH 6000 gathering data at the new summit position of The Pimple, with the old position of the summit in the ploughed field in the background of this photograph |
For details on the survey that relocated the summit of this hill please click {here}
Myrddyn Phillips (October 2015)
Mapping Mountains - Summit Relocations - 100m Twmpau
Cae Boncyn (SJ 238 193) - 2nd summit relocation
Survey post for Cae Boncyn
Significant Name Changes post for Cae Boncyn
There has been a Summit Relocation initiated by a survey with the Trimble GeoXH 6000 to the listing of 100m Twmpau (thirty welsh metre prominences and upward), with the following details being retrospective as the survey that resulted in this summit relocation was conducted on 8th August 2015.
The survey was conducted in the lower hills of the Carnedd Wen range, centred between the small towns of Llansanffraid-ym-Mechain to the hill’s north-west, Llanymynech to the hill’s north-east and Four Crosses to the hill’s south-east, with all three communities being situated beside or close to the Afon Efyrnwy (River Vyrnwy).
The hill was surveyed in the company of Alex Cameron during a multi hill bagging day in lovely sunshine as we visited nine P30 Twmpau hills with seven of them being Trimbled.
The hill is unnamed on current Ordnance Survey maps, having been listed as Bryn y Gelli in the original P30 lists that appeared on Geoff Crowder’s v-g.me website. This was an invented name partly taken from the farm which is situated just to the south-west of the summit. However, when we visited the hill we asked Mel Jones at Gelli Farm for permission to do so and also made enquiries concerning the name of the hill, Mel produced a field map of Gelli Farm with the field where the summit of the hill is situated named as Cae Boncyn, unsurprisingly this is also the name that Mel gave us for the highest field.
Prior to the survey with the Trimble GeoXH 6000 the position of the summit was listed as that of its 142m spot height which is situated at SJ 23882 19312. This spot height is positioned in an adjacent field to where the highest part of the hill is situated, the distance between these two positions is not great but a relocation of a summit to a different field is important and therefore this information warrants a post under the heading of Summit Relocations.
The position of the relocated summit is at SJ 23849 19306 and is the top of a small hillock, hence the Boncyn part of its name, this is not given a spot height on current Ordnance Survey maps but the survey result produced by the Trimble gave it as 142.1m (converted to OSGM15) and approximately 30-40 metres westward from the position of the spot height on Ordnance Survey maps.
The full details for the hill are:
Cardinal Hill: Carnedd Wen
Summit Height: 142.1m (converted to OSGM15)
Name: Cae Boncyn
OS 1:50,000 map: 126
Summit Grid Reference (New Position): SJ 23849 19306
Drop: 44m
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| The Trimble GeoXH 6000 gathering data at the new summit position of Cae Boncyn, with the old position of the summit in the adjacent field beyond the wooden fence in the background of this photo |
For details on the survey that relocated the summit of this hill please click {here}
Myrddyn Phillips (August 2015)
Mapping Mountains - Summit Relocations - 100m Twmpau
Gravel Pit Field (SJ 225 167) - 1st summit relocation
Survey post for Gravel Pit Field
Significant Name Changes post for Gravel Pit Field
There has been a Summit Relocation to the listing of 100m Twmpau (thirty welsh metre prominences and upward) hills due to a survey with the Trimble GeoXH 6000, and these details are retrospective as the survey that resulted in this summit relocation was conducted on 8th August 2015.
The survey was conducted in the lower hills of the Carnedd Wen range, between the small communities of Deuddwr and Collfryn, these are situated between the A495 to the west and the A483 to the east.
The hill was surveyed in the company of Alex Cameron during a multi hill bagging day when the sun beat down and we visited nine P30 Twmpau hills with seven of them being Trimbled.
The name of the land where the summit of this hill is situated is Gravel Pit Field and this was derived from the Tithe map, with the hill having been listed as The Mount in the original P30 lists that appeared on Geoff Crowder’s v-g.me website, this was a name taken from the farm which is situated southward of this hill's summit.
Prior to the survey with the Trimble GeoXH 6000 the position of the summit was listed as that of its triangulation pillar which is submerged in a hedge beside a narrow country lane. This trig pillar has a 153.951m flush bracket height adjoined to it and is given the rounded up height of 154m on current Ordnance Survey maps, with its flush bracket given the position of SJ 22556 16673 in the OS Trig Database. However, higher ground exists on the opposite side of the lane in a field.
The position of the relocated summit is at SJ 22598 16703 and is the top of featureless ground a few metres from a hedge in a field, this is not given a spot height on current Ordnance Survey maps but the survey result with the Trimble gave it as 0.99m higher than the flush bracket on the triangulation pillar and approximately 50 metres north-eastward from where it stands in a hedge.
The full details for the hill are:
Cardinal Hill: Carnedd Wen
Summit Height: 154.9m (converted to OSGM15)
Name: Gravel Pit Field
OS 1:50,000 map: 126
Summit Grid Reference (New Position): SJ 22598 16703
Drop: c 47m
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| The Trimble GeoXH 6000 gathering data at the new summit position of Gravel Pit Field, with the old position of the summit opposite the gate in the centre right of this photograph |
For details on the survey that relocated the summit of this hill please click {here}
Myrddyn Phillips (August 2015)
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