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: 

Pant y Brwynog (SN 548 037) - 100m Sub-Twmpau addition

Cae'r Lloi Mawr (SH 507 390) - Welsh P15 reclassified to Welsh Sub-P15

Pt. 277.7m (SO 106 406) - 200m Sub-Twmpau addition

Llan Ucha Castell Madog (SO 027 385) - Sub-Trichant deletion

Pen y Coed (SN 569 049) - 30-99m Sub-Twmpau addition

Cae Tŷ Coch (SO 095 413) - 200m Sub-Twmpau addition

 

Significant Height Revisions: 

Tryfan (SH 597 578) - 500m Twmpau and Welsh Highlands - Uchafion Cymru

Tryfan (SH 596 580) - 500m Twmpau and Welsh Highlands - Uchafion Cymru

Pant y Brwynog (SN 548 037) - 100m Twmpau

Pt. 277.7m (SO 106 406) - 200m Twmpau

Pen Rhiw Einon (SO 075 380) - Y Trichant - The 300m Hills of Wales

Foel Fras (SH 696 681) - 900m Twmpau, Welsh Highlands - Uchafion Cymru and Y Pellennig - The Remotest Hills of Wales

Coed Bryn Twr (SH 539 400) - Welsh P15s

 

 

Summit Relocations: 

Yr Allt (SN 552 024) - 30-99m Twmpau

Pant y Brwynog (SN 548 037) - 100m Twmpau

Pen y Coed (SN 569 049) - 30-99m Twmpau

Foel Fras (SH 696 681) - 900m Twmpau, Welsh Highlands - Uchafion Cymru and Y Pellennig - The Remotest Hills of Wales

 

Significant Name Changes: 

Cae Eithin (SO 096 286) - Welsh P15s

Trehenry Fawr (SO 097 343) - 200m Twmpau

Mynydd Fforest (SO 086 389) - Y Trichant - The 300m Hills of Wales

Pen y Castell (SJ 117 095) - 200m Twmpau and Y Trechol - The Dominant Hills of Wales

Yr Allt (SN 552 024) - 30-99m Twmpau

Great Beech (SO 320 014) - 100m Twmpau and Y Trechol - The Dominant Hills of Wales

Cae'r Lloi Mawr (SH 507 390) - Welsh P15s

Bryn Golau (SH 511 392) - Welsh P15s

Pt. 277.7m (SO 106 406) - 200m Twmpau

Ale Oak Bank (SO 224 835) - The Fours - The 400m Hills of England

Pen Rhiw Einon (SO 075 380) - Y Trichant - The 300m Hills of Wales

Pant y Brwynog (SN 548 037) - 100m Twmpau

 

Mapping Mountains – Hill Reclassifications – 200m Twmpau

 

Cae Tŷ Coch (SO 095 413) – 200m Sub-Twmpau addition 

There has been confirmation of an addition to the list of 200m 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 Cae Tŷ Coch (SO 095 413)

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

200m Twmpau – Welsh hills at or above 200m and below 300m in height that have 30m minimum drop, with an accompanying sub list entitled the 200m Sub-Twmpau, with the criteria for this sub category being all Welsh hills at or above 200m and below 300m 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. 

200m Twmpau by Myrddyn Phillips

The name the hill is now listed by is Cae Tŷ Coch and this was derived from the Tithe map, and it is adjoined to the Mynydd Epynt group of hills, which are situated in the central part of South Wales (Region B, Sub-Region B1), and it is positioned with a minor road to its west and south-east, and the A470 road to its north-east, and has the small community of Erwyd (Erwood) towards the north.

When the original 200m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was not included in the accompanying 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 20m of drop, based on the 282m summit spot height that appears on the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and an estimated c 262m bwlch height, based on interpolation of 10m contouring between 260m – 270m. 

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 confirmation of the addition of this hill to 200m Sub-Twmpau status is due to LIDAR analysis, resulting in a 282.7m summit height and a 260.65m bwlch height, with these values giving this hill 22.0m of drop, which is sufficient for it to be classified as a 200m Sub-Twmpau. 

 

The full details for the hill are: 

Group:  Mynydd Epynt 

Name:  Cae Tŷ Coch 

OS 1:50,000 map:  161

Summit Height:  282.7m (LIDAR) 

Summit Grid Reference:  SO 09549 41332 (LIDAR) 

Bwlch Height:  260.65m (LIDAR) 

Bwlch Grid Reference:  SO 09124 41273 (LIDAR) 

Drop:  22.0m (LIDAR) 

 

Myrddyn Phillips (August 2024)

 

 

 

 

Mapping Mountains – Significant Height Revisions – The Welsh P15s

Coed Bryn Twr (SH 539 400) 

There has been a Significant Height Revision to a hill that is listed in The Welsh P15s, 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 Bryn Twr (SH 539 400)

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

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

The Welsh P15s by Myrddyn Phillips

The name the hill is listed by is Coed Bryn Twr, and it is adjoined to the Moel Hebog group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with a minor road and the A487 road to its north and the A497 road to its south, and has the town of Porthmadog towards the east south-east.

When the listing that became known as The Welsh P15s was being compiled, this hill was included in the main P15 list with an estimated c 19m of drop, based on the 66m summit spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map and an estimated c 47m bwlch height, based on interpolation of 10m contouring between 40m – 50m. 

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 Bryn Twr (SH 539 400)

The summit height produced by LIDAR analysis is 63.7m and when compared to detail on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map, 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 or Harvey 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 to the data produced by the Trimble or by LIDAR analysis.

Therefore, the new listed summit height of this hill is 63.7m and this was derived from LIDAR analysis.  This is 2.3m lower than the 66m spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage. 

 ills of Wales, and are reproduced below@

The full details for the hill are: 

Group:  Moel Hebog 

Name:  Coed Bryn Twr 

OS 1:50,000 map:  124

Summit Height (New Height):  63.7m (LIDAR)                                                           

Summit Grid Reference:  SH 53944 40079 (LIDAR) 

Bwlch Height:  46.3m (LIDAR) 

Bwlch Grid Reference:  SN 53944 40155 (LIDAR) 

Drop:  17.4m (LIDAR) 

 

Myrddyn Phillips (August 2024)

 

 

 

  

Mapping Mountains – Significant Name Changes – 100m Twmpau

 

Pant y Brwynog (SN 548 037) 

There has been a Significant Name Change 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. 

LIDAR image of Pant y Brwynog (SN 548 037)

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

100m Twmpau – Welsh hills at or above 100m and below 200m in height that have 30m minimum drop, with an accompanying sub list entitled the 100m Sub-Twmpau, with the criteria for this sub category being all Welsh hills at or above 100m and below 200m in height with 20m or more and below 30m of drop, with the word Twmpau being an acronym standing for thirty welsh metre prominences and upward. 

100m Twmpau by Myrddyn Phillips

The hill is adjoined to the Mynydd Sylen group of hills, which are situated in the southern part of South Wales (Region B, Sub-Region B5), and it is positioned with minor roads to its north-east, west and south, and the A476 road farther to its west, the A4138 road to its south-east and the M4 motorway farther to its east, and has the town of Pontarddulais towards the east.

When the original 100m 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-assessed and it was listed under the point (Pt. 130m) notation with an estimated c 27m of drop, based on the 130m summit spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map and an estimated c 103m bwlch height, based on interpolation of 5m contouring between 100m – 105m. 

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

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

Extract from the Tithe map

The enclosed land where the summit of this hill is situated is given the number 73 on the Tithe map, this can be cross referenced against the apportionments; it is these apportionments that give the name of the owner or occupier of the land as well as the name of the land.  The land where the summit of this hill is situated is named as Pant y Brwynog in the apportionments, with the details on the Tithe map appearing in the parish of Llangennech and in the county named as Carmarthen. 

Extract from the apportionments

Therefore, the name this hill is now listed by in the 100m Twmpau is Pant y Brwynog, and this was derived from the Tithe map. 

 

The full details for the hill are:

Group:  Mynydd Sylen

Name:  Pant y Brwynog

Previously Listed Name:  Pt. 130m   

OS 1:50,000 map:  159

Summit Height:  127.65m (LIDAR) 

Summit Grid Reference:  SN 54886 03732 (LIDAR) 

Bwlch Height:  102.6m (LIDAR) 

Bwlch Grid Reference:  SN 54795 03991 (LIDAR) 

Drop:  25.0m (LIDAR) 

 

Myrddyn Phillips (August 2024)

 

 

 

 

Mapping Mountains – Summit Relocations – Y Pellennig – The Remotest Hills of Wales, Welsh Highlands – Uchafion Cymru and 900m Twmpau

 

Foel Fras (SH 696 681) 

There has been a Summit Relocation to a hill that is listed in the Y Pellennig – The Remotest Hills of Wales, Welsh Highlands – Uchafion Cymru and 900m Twmpau, with the summit height, bwlch height and their locations, the drop and status of the hill derived from a Leica RX1250 survey conducted by Alan Dawson. 

Foel Fras (SH 696 681) from the summit of Trwsgl (SH 663 679)

The criteria for the three listings that this summit relocation applies to are:

Y Pellennig –The Remotest Hills of Wales - Welsh hills whose summit is at least 2.5km from the nearest paved public road and the hill has a minimum 15m of drop.  The list is co-authored by Myrddyn Phillips and Aled Williams and is available as a downloadable e-booklet or print-booklet version on Mapping Mountains Publications with the up-to-date master list available on Mapping Mountains to download in Google Doc format. 

Y Pellennig - The Remotest Hills of Wales by Myrddyn Phillips and Aled Williams

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

900m Twmpau - Welsh hills at or above 900m and below 1000m in height with 30m minimum drop, with an accompanying sub list entitled the 900m Sub-Twmpau with the criteria for this sub category being all Welsh hills at or above 900m and below 1000m 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 list is authored by Myrddyn Phillips and is available to download in Google Doc format from Mapping Mountains.

900m Twmpau by Myrddyn Phillips

The name the hill is listed by is Foel Fras and it is adjoined to the Carnedd Llywelyn 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 A55 road to its north-west, the A5 road to its south-west and the B5106 and A470 roads to its east, and has the town of Bethesda towards the west south-west. 

When the original list that later became known as the Welsh Highlands – Uchafion Cymru was first compiled, this hill was listed with 58m of drop, based on the 942m summit spot height adjoined to a triangulation pillar positioned at SH 69652 68173 that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map, and the 884m bwlch spot height that appears on the Ordnance Survey 1:25,000 Explorer map.

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

However, the summit area of this hill is rocky and includes a number of substantial upright rock spikes.  One of the earliest Abney Level surveys to ascertain the high point of this hill was conducted in 2011 by Graham Jackson.  This survey concluded that a rock spike approximately 55 metres south-wesward of the trig pillar is the highest point of this hill. 

This rock spike was subsequently surveyed by Alan Dawson using the Leica RX1250, resulting in a 944.1m summit height positioned at SH 69611 68118, 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 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.

The Leica RX1250 gathering data at the summit of Foel Fras (SH 696 681).  Photo: Alan Dawson  

Therefore, the new listed summit height of this hill is 944.1m and this is positioned at SH 69611 68118 and this was derived from a Leica RX1250 survey, this position is approximately 55 metres south-westward from where the triangulation pillar is positioned and importantly it is positioned to a different feature.

 

ills of Wales, and are reproduced below@

The full details for the hill are:

Group:  Carnedd Llywelyn

Name:  Foel Fras

OS 1:50,000 map:  115

Summit Height:  944.1m (converted to OSGM15, Leica RX1250) 

Summit Grid Reference (New Position):  SH 69611 68118 (Leica RX1250) 

Bwlch Height:  881.3m (converted to OSGM15, Leica RX1250) 

Bwlch Grid Reference:  SH 68799 66515 (Leica RX1250) 

Drop:  62.8m (Leica RX1250) 

Remoteness:  3.975km

 

Myrddyn Phillips and Aled Williams (August 2024)