Monthly Synopsis

 

Synopsis of all major changes detailed on Mapping Mountains during the last calendar month.  These can include new, confirmation and retrospective changes

 

Hill Reclassifications: 

Pen Tyrau (SH 837 382) - Welsh Highland Sub addition

Parc (SH 755 006) - 30-99m Sub-Twmpau addition

Y Faerdre (SH 784 795) - Welsh Sub-P15 deletion

Pt. 914.9m (SH 659 585) - Welsh Highland Sub addition

Belan Hill (SO 051 901) - Sub-Trichant deletion

Cae Cownog (SJ 111 135 & SJ 112 135) - 200m Sub-Twmpau addition

Stile Crag (NY 761 986) - Sub-Four addition

Coed y Fedw (SN 677 947) - 30-99m Sub-Twmpau addition

Buck Fell (NY 594 906) - Sub-Four addition

Elidir Fach (SH 603 613) - Welsh Highland Sub addition

Significant Height Revisions: 

Y Faerdre (SH 784 795) - The Welsh P15s

Pt. 914.9m (SH 659 585) - Welsh Highlands - Uchafion Cymru

Coed y Fedw (SN 677 947) - 30-99m Twmpau

Summit Relocations: 

Blackkip (NT 799 043) - The Fours - The 400m Hills of England

Coed Garth Gwynion (SN 733 986) - 200m Twmpau and Y Trechol - The Dominant Hills of Wales

Graig y Barcut (SN 546 027) - 100m Twmpau

Gorn Hill (SN 968 844) - Y Trichant - The 300m Hills of Wales

Cae Cownog (SJ 111 135 & SJ 112 135) - 200m Twmpau

Bryn Posteg Hill (SN 960 822) - Y Trichant - The 300m Hills of Wales

Significant Name Changes: 

Cefn Lladron (SO 058 908) - Y Trichant - The 300m Hills of Wales

Cefn (SH 721 004) - 100m Twmpau and Y Trechol - The Dominant Hills of Wales

Comin Gwauncaegurwen (SN 738 129) - 100m Twmpau

Cae Pen Crugiau (SN 412 371) - 200m Twmpau

Parc (SH 755 006) - 30-99m Twmpau

Coed Garth Gwynion (SN 733 986) - 200m Twmpau and Y Trechol - The Dominant Hills of Wales

Graig y Barcut (SN 546 027) - 100m Twmpau

Y Faerdre (SH 784 795) - The Welsh P15s

Mapping Mountains – Significant Height Revisions – 30-99m Twmpau

 

Coed y Fedw (SN 677 947) 

There has been a Significant Height Revision to a hill that is listed in the 30-99m Twmpau, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Coed y Fedw (SN 677 947)

The criteria for the list that this height revision applies to are:

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

30-99m Twmpau by Myrddyn Phillips

The name the hill is listed by is Coed y Fedw, and it is adjoined to the Banc Llechwedd Mawr group of hills, which are situated in the northern part of South Wales (Region B, Sub-Region B1), and it is positioned with the A487 road to its south-east, and has the small community of Ffwrnais (Furnace) towards the east north-east.

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

After the sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-evaluated and it was listed with an estimated c 22m of drop, based on an estimated c 46m summit height and an estimated c 24m bwlch height, with both heights based on interpolation of 10m contouring. 

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 summit image of Coed y Fedw (SN 677 947)

The summit height produced by LIDAR analysis is 49.6m and is positioned at SN 67780 94773, and this comes within the parameters of the Significant Height Revisions used within this page heading, these parameters are:

The term Significant Height Revisions applies to any listed hill whose interpolated height and Ordnance Survey, Harvey or other interactive map summit spot height has a 2m or more discrepancy when compared to the survey result produced by the Trimble GeoXH 6000 or analysis of data produced via LIDAR.  Also included are hills whose summit map data is missing an uppermost ring contour when compared with the data produced by the Trimble or by LIDAR analysis.

Therefore, the new listed summit height of this hill is 49.6m and this was derived from LIDAR analysis, this is 3.6m higher than the previously listed summit height of c 46m, which was based on interpolation of its uppermost 40m ring contour that appears on the Ordnance Survey 1:25,000 Explorer map.

 

ills of Wales, and are reproduced below@

The full details for the hill are:

Group:  Banc Llechwedd Mawr 

Name:  Coed y Fedw 

OS 1:50,000 map:  135

Summit Height (New Height):  49.6m (LIDAR) 

Summit Grid Reference:  SN 67780 94773 (LIDAR)               

Bwlch Height:  22.1m (LIDAR) 

Bwlch Grid Reference:  SN 67635 94495 (LIDAR) 

Drop:  27.5m (LIDAR) 

               

Myrddyn Phillips (November 2024)

 

 

 

 

Mapping Mountains – Summit Relocations – Y Trichant – The 300m Hills of Wales

 

Bryn Posteg Hill (SN 960 822) 

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

LIDAR image of Bryn Posteg Hill (SN 960 822)

The criteria for the list that this summit relocation applies to:

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

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

The name the hill is listed by is Bryn Posteg Hill, and it is adjoined to the Hirddywel group of hills, which are situated in the northern part of South Wales (Region B, Sub-Region B2), and it is positioned with the B4518 road to its east and north, the A470 road to its west and a minor road to its south, and has the town of Llanidloes towards the north.

When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was included in the main P30 list with a c 370m summit height, based on non interpolation of its uppermost contour that appears on the Ordnance Survey 1:25,000 Exlorer map.  The summit height was subsequently amended to 371m and its position given as SN 96025 82266. 

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 gives the highest ground on this hill as 371.5m positioned at SN 96027 82264.  However, this is a part of a raised hedgebank 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. 

LIDAR summit image of Bryn Posteg Hill (SN 960 822)

The height produced by LIDAR analysis to the natural summit of this hill is 370.7m positioned at SN 96020 82261, and this position in relation to the raised hedgebank boundary 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 either on Ordnance Survey maps or interactive mapping, 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 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 370.7m and this is positioned at SN 96020 82261, 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 7 metres south-westward from where the high point of the raised hedgebank boundary is positioned. 

 

The full details for the hill are:

Group:  Hirddywel 

Name:  Bryn Posteg Hill 

OS 1:50,000 map:  136

Summit Height:  370.7m (LIDAR)                                                           

Summit Grid Reference (New Position):  SN 96020 82261 (LIDAR) 

Bwlch Height:  326.7m (LIDAR) 

Bwlch Grid Reference:  SN 96584 82501 (LIDAR) 

Drop:  44.0m (LIDAR) 

 

Myrddyn Phillips (November 2024)

Mapping Mountains – Hill Reclassifications – Welsh Highlands – Uchafion Cymru

 

Elidir Fach (SH 603 613) – Welsh Highland Sub reinstatement 

There has been a reinstatement to the listing of the Welsh Highlands – Uchafion Cymru, with the summit height, bwlch height and their locations, the drop and status of the hill derived from a Trimble GeoXH 6000 survey conducted by Aled Williams. 

The summit area of Elidir Fach (SH 603 613).  Photo: Aled Williams

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

Welsh Highlands – Uchafion Cymru – Welsh hills at or above 500m in height with 15m minimum drop, with an accompanying sub list entitled the Welsh Highland Subs, the criteria for which is all Welsh hills at or above 500m in height with 10m or more and below 15m of drop.  This list is authored by Myrddyn Phillips and Aled Williams with the Introduction to the list published on Mapping Mountains in November 2015 and the latest update relating to the list published on Mapping Mountains in January 2023.

Welsh Highlands - Uchafion Cymru by Aled Williams and Myrddyn Phillips

The name the hill is listed by is Elidir Fach and it is adjoined to the Glyder Fawr group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with minor roads to its north and west, the A5 road to its north-east and the A4086 road to its south-west, and has the village of Llanberis towards the south-west. 

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

When the initial P10 sub list was completed in June 2020 this hill was listed as a Welsh Highland Sub with 13.5m of drop, based on a basic levelling survey conducted by Myrddyn Phillips on the 22.05.98, and listed with an estimated c 800m summit height relative to its bwlch height, and a 786m bwlch height, with the latter based on detail on the enlarged-scale Ordnance Survey map hosted on the coflein.gov.uk website. 

LIDAR image of Elidir Fach (SH 603 613)

The hill was subsequently analysed via LIDAR by Aled Williams, resulting in a 794.5m summit height and a 784.7.1m bwlch height, with these values giving this hill 9.8m of drop, which was insufficient for it to be classified as a Welsh Highland Sub.  However, with the drop value relatively close to the qualifying criterion of 10m this hill was prioritised for a survey with the Trimble GeoXH 6000. 

The bwlch area of Elidir Fach (summit at SH 603 613).  Photo: Aled Williams

Therefore, the reinstatement of this hill to Welsh Highland Sub status is due to a Trimble GeoXH 6000 survey, resulting in a 794.2m summit height and a 784.2m bwlch height, with these values giving this hill 10.0m of drop, which is sufficient for it to be classified as a Welsh Highland Sub. 

 

The full details for the hill are: 

Group:  Glyder Fawr

Name:  Elidir Fach           

OS 1:50,000 map:  115

Summit Height:  794.2m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SH 60377 61341 (Trimble GeoXH 6000)

Bwlch Height:  784.2m (converted to OSGM15, Trimble GeoXH 6000)

Bwlch Grid Reference:  SH 60556 61279 (Trimble GeoXH 6000)   

Drop:  10.0m (Trimble GeoXH 6000) 

 

For the additions, deletions and reclassifications to the Welsh Highlands – Uchafion Cymru reported on Mapping Mountains please consult the following Change Registers:

 

Welsh Highland P15s

 

Welsh Highland Subs

 

Aled Williams and Myrddyn Phillips (November 2024)

 

 

 

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

 

Buck Fell (NY 594 906) – Sub-Four addition

There has been an addition to the listing of the The Fours – The 400m Hills of England, with the summit height, col height and their locations, the drop and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Buck Fell (NY 594 906)

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

The Fours – The 400m Hills of England - English hills at or above 400m and below 500m in height that have 30m minimum drop, accompanying the main list is a sub list entitled the Sub-Fours, the criteria for which are all English hills at or above 400m and below 500m in height that have 15m or more and below 30m of drop.  The list is co-authored by Myrddyn Phillips and Aled Williams and is available to download in Google Doc format from the Mapping Mountains site.

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

The name the hill is listed by is Buck Fell, and it is adjoined to the Sighty Crag group of hills, which are situated in the north-east of the country close to the border with Scotland, and it is positioned with the B6357 road to its west and a minor road t0 its east, and has the village of Butteryhaugh towards the north-east.

When the Introduction to the first group of hills for the updated and revised listing of the The Fours – The 400m Hills of England was published by Mapping Mountains on the 10^th September 2022, it was announced that the accompanying sub lists were being revised with the two 390m categories dispensed with and the criteria and name of the 400m Sub-Fours revised.  The one accompanying sub list is now named the Sub-Fours with its criteria being all English hills 400m and above and below 500m in height that have 15m and more and below 30m of drop.

Prior to this revision this hill was listed with 14m of drop, based on the 402m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and the 388m col spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map. 

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.

Therefore, the addition of this hill to Sub-Four status is due to LIDAR analysis, resulting in a 401.7m summit height and a 386.5m col height, with these values giving this hill 15.3m of drop, which is sufficient for it to be classified as a Sub-Four.

 

The full details for the hill are:

Group:  Sighty Crag

Name:  Buck Fell

OS 1:50,000 map:  80

Summit Height:  401.7m (LIDAR)

Summit Grid Reference:  NY 59457 90613 (LIDAR)

Col Height:  386.5m (LIDAR)

Col Grid Reference:  NY 59296 90959 (LIDAR)

Drop:  15.3m (LIDAR)

 

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

 

The Fours

 

Sub-Fours

 

Myrddyn Phillips and Aled Williams (November 2024)