Thursday 31 March 2022

Mapping Mountains – Hill Reclassifications – 200m Twmpau


Wern Ddu (SN 734 366) – 200m Sub-Twmpau reclassified to 200m Twmpau

There has been confirmation of a reclassification 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 Wern Ddu (SN 734 366)

The criteria for the list that this reclassification 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. 

The 200m Twmpau by Myrddyn Phillips

The name the hill is now listed by is Wern Ddu 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 encircled by minor roads, with the A482 road farther to its west and the A40 road farther to its south-east, and has the town of Llanymddyfri (Llandovery) towards the south-east. 

When the original 200m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was included in the Hills to be surveyed sub list that accompanied the main P30 list, as it was considered not to meet the criteria then used for the main P30 category. 

When 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 33m of drop, based on the 208m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 175m bwlch height, based on interpolation of 10m contouring between 170m – 180m. 

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 reclassification of this hill from 200m Sub-Twmpau status is due to LIDAR analysis, resulting in a 207.9m summit height and a 171.5m bwlch height, with these values giving this hill 36.4m of drop, which is sufficient for it to be classified as a 200m Twmpau. 

 

The full details for the hill are: 

Group:  Mynydd Mallaen 

Name:  Wern Ddu 

OS 1:50,000 map:  146, 160

Summit Height:  207.9m (LIDAR) 

Summit Grid Reference:  SN 73474 36636 (LIDAR) 

Bwlch Height:  171.5m (LIDAR) 

Bwlch Grid Reference:  SN 73922 36372 (LIDAR) 

Drop:  36.4m (LIDAR) 

 

Myrddyn Phillips (March 2022)

 

 

 

 

  

Wednesday 30 March 2022

Mapping Mountains – Significant Name Changes – Y Trichant – The 300m Hills of Wales


Ffridd (SH 727 045) 

There has been a Significant Name Change 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 detail on contemporary maps produced from Ordnance Survey data. 

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

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 13th May 2017, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

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

The hill is adjoined to the Tarren y Gesail group of hills, which are situated in the south-western part of North Wales (Region A, Sub-Region A3), and it is positioned with the A493 road to its south and the A487 road to its east, and has the town of Machynlleth towards the south south-east. 

When the original 300m 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. 

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-evaluated and it was listed under the point (Pt. 332m) notation with 18m of drop, based on the 332m summit spot height and the 314m bwlch spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage 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 224 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 Ffridd in the apportionments, with the details on the Tithe map appearing in the parish of Pennal and in the county named as Merioneth. 

Extract from the apportionments

Therefore, the name this hill is now listed by in the Y Trichant – The 300m Hills of Wales is Ffridd and this was derived from the Tithe map.

 

The full details for the hill are: 

Group:  Tarren y Gesail 

Name:  Ffridd 

Previously Listed Name:  Pt. 332m 

OS 1:50,000 map:  135

Summit Height:  332m (spot height)                                                           

Summit Grid Reference:  SH 72758 04535 (spot height) 

Bwlch Height:  c 312m (interpolation) 

Bwlch Grid Reference:  SH 72624 04549 (interpolation) 

Drop:  c 20m (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (March 2022)

 

 

 

 

 

 

 

 

 

  

Tuesday 29 March 2022

Mapping Mountains – Significant Name Changes – 200m Twmpau and Y Trechol – The Dominant Hills of Wales

 

Penlan (SN 744 367) 

There has been a Significant Name Change to a hill that is listed in the 200m 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. 

LIDAR image of Penlan (SN 744 367)

The criteria for the two listings that this name change 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. 

The 200m 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. 

Y Trechol - The Dominant Hills of Wales by Myrddyn Phillips

The hill appeared in the original Welsh 200m P30 list on Geoff Crowder’s v-g.me website, under the invented and transposed name of Banc Penlan, with an accompanying note stating; Name from buildings to the South-East.


Banc Penlan233mSN744367146/160187Name from buildings to the South-East

 

During my early hill listing I thought it appropriate to either invent a name for a hill, or use a name that appeared near to the summit of the hill on Ordnance Survey maps of the day.  My preference was to use farm names and put Pen, Bryn or Moel in front of them or as in this instance transpose the name of a farm and add the word Banc to it.  This is not a practice that I now advocate as with time and inclination place-name data can be improved either by asking local people or by examining historic documents, through this form of research an appropriate name for the hill can usually be found. 

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 170 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 a part of Penlan in the apportionments, with the details on the Tithe map appearing in the parish of Cil-y-cwm and in the county named as Carmarthen. 

Extract from the apportionments

Therefore, the name this hill is now listed by in the 200m Twmpau and Y Trechol – The Dominant Hills of Wales is Penlan and this was derived from the Tithe map. 

 

The full details for the hill are:

Group:  Mynydd Mallaen

Name:  Penlan

Previously Listed Name:  Banc Penlan   

OS 1:50,000 map:  146, 160

Summit Height:  232.2m (LIDAR) 

Summit Grid Reference:  SN 74453 36723 (LIDAR) 

Bwlch Height:  148.7m (LIDAR) 

Bwlch Grid Reference:  SN 73276 37121 (LIDAR) 

Drop:  83.5m (LIDAR) 

Dominance:  35.98% (LIDAR) 

 

Myrddyn Phillips (March 2022)

 

 

 

Monday 28 March 2022

Mapping Mountains – Hill Reclassifications – Y Trichant – The 300m Hills of Wales

 

Ffridd (SH 727 045) – Sub-Trichant addition

There has been an addition to the list of 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 detail on contemporary maps produced from Ordnance Survey data. 

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

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 13th May 2017, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022. 

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

The name the hill is listed by is Ffridd and this was derived from the Tithe map, and it is adjoined to the Tarren y Gesail group of hills, which are situated in the south-western part of North Wales (Region A, Sub-Region A3), and it is positioned with the A493 road to its south and the A487 road to its east, and has the town of Machynlleth towards the south south-east. 

When the original 300m 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. 

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. 

After the sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-evaluated against the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map.  This mapping had many spot heights not on other publicly available maps and for this hill it had a 332m summit spot height which matches the spot height given on the Ordnance Survey 1:50,000 Landranger map, and a 314m spot height on the area of the bwlch, with the latter positioned at SH 72590 04546, with these values giving this hill 18m of drop. 

Extract from the Ordnance Survey 1:50,000 Landranger map

One of the resources recently available online is the mapping on the OS Maps website and the details for this hill were subsequently re-assessed against this mapping.  This is the replacement for OS Get-a-map and until recent times had contours at 5m intervals which were proving consistently more accurate compared to the 5m contours that sometimes appear on the Ordnance Survey 1:25,000 Explorer map and used to appear on the online Vector Map Local.  This mapping had bwlch contouring between 310m – 315m, with interpolation placing the height of the bwlch as an estimated c 312m, with these contours also represented on other 5m contouring available online.  This estimated height is now prioritised over the 314m spot height on the old Interactive Coverage Map which 5m contouring positions on the upward slope on the hill to hill traverse and therefore not at the critical point of the bwlch. 

Extract from the interactive 5m contouring

Therefore, the addition of this hill to Sub-Trichant status is due to detail on contemporary maps produced from Ordnance Survey data, resulting in a 332m summit height and an estimated c 312m bwlch height, with these values giving this hill an estimated c 20m of drop, which is sufficient for it to be classified as a Sub-Trichant. 

 

The full details for the hill are: 

Group:  Tarren y Gesail 

Name:  Ffridd 

OS 1:50,000 map:  135

Summit Height:  332m (spot height)                                                           

Summit Grid Reference:  SH 72758 04535 (spot height) 

Bwlch Height:  c 312m (interpolation) 

Bwlch Grid Reference:  SH 72624 04549 (interpolation) 

Drop:  c 20m (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (March 2022)

 

 

Sunday 27 March 2022

Mapping Mountains – Significant Name Changes – 200m Twmpau and Y Trechol – The Dominant Hills of Wales

 

Y Lan (SN 737 340) 

There has been a Significant Name Change to a hill that is listed in the 200m 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. 

LIDAR image of Y Lan (SN 737 340)

The criteria for the two listings that this name change 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. 

The 200m 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. 

Y Trechol - The Dominant Hills of Wales by Myrddyn Phillips

The hill appeared in the original Welsh 200m P30 list on Geoff Crowder’s v-g.me website, under the transposed name of Allt Ddu, which is a prominent name that appears north-west of the summit of this hill on the Ordnance Survey 1:25,000 Explorer map.


Allt Ddu244mSN73934014612/187Clem/Yeaman. Trig pillar.

 

During my early hill listing I paid little regard to name placement on the map, or the meaning of names and to what feature the name was appropriately applied to.  Therefore, I prioritised names for listing purposes that I now understand are either inappropriate or where another name is viewed as being more appropriate, with the previously listed name of Allt Ddu applicable to land that does not take in the summit of this hill. 

This is not a practice that I now advocate as with time and inclination place-name data can be improved either by asking local people or by examining historic documents, through this form of research an appropriate name for the hill can usually be found. 

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 455 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 Y Lan in the apportionments, with the details on the Tithe map appearing in the parish of Llandingad and in the county named as Carmarthen. 

Extract from the apportionments

Therefore, the name this hill is now listed by in the 200m Twmpau and Y Trechol – The Dominant Hills of Wales is Y Lan and this was derived from the Tithe map. 

 

The full details for the hill are:

Group:  Mynydd Mallaen

Name:  Y Lan

Previously Listed Name:  Allt Ddu   

OS 1:50,000 map:  146, 160

Summit Height:  244.4m (LIDAR) 

Summit Grid Reference:  SN 73776 34010 (LIDAR) 

Bwlch Height:  135.75m (LIDAR) 

Bwlch Grid Reference:  SN 74333 34767 (LIDAR) 

Drop:  108.6m (LIDAR) 

Dominance:  44.45% (LIDAR) 

 

Myrddyn Phillips (March 2022)