Mapping Mountains – Hill Reclassifications – Y Trechol – The Dominant Hills of Wales

Cymin (SO 527 125) – Lesser Dominant addition

There has been an addition to the listing of Y Trechol – The Dominant Hills of Wales, with the summit height, bwlch height, their locations, the drop, dominance and status of the hill confirmed by LIDAR analysis conducted by Myrddyn Phillips.

LIDAR image of Cymin (SO 527 125)

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

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 3^rd 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 Cymin and it is adjoined to the Fforest y Ddena 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 A4136 road to its north and the A466 road to its south-west, and has the town of Trefynwy (Monmouth) towards the west.

When the original 200m height band of Welsh P30 hills published on Geoff Crowder’s v-g.me website were standardised and interpolated heights also included, this hill was listed with c 86m of drop and 33.46% dominance, based on an estimated c 257m summit height and an estimated c 171m bwlch height, with these heights estimated from interpolation of 5m contouring that appears on the Ordnance Survey 1:25,000 Outdoor Leisure (latterly Explorer) map.

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 256m spot height on the area of this hill’s summit positioned at SO 527 125, and when coupled with the estimated c 171m bwlch height, these values give this hill c 85m of drop and 33.20% dominance, resulting in its deletion from Lesser Dominant status.  The 256m spot height is also shown on Ordnance Survey data that appears on the Magic Maps website.

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. 

LIDAR image of Cymin

Therefore, the addition of this hill to Lesser Dominant status is due to LIDAR analysis, resulting in a 256.4m summit height and a 170.6m bwlch height, with these values giving this hill 85.8m of drop and 33.47% dominance, which is sufficient for this hill to be reinstated to Lesser Dominant status.

The full details for the hill are:

Group:  Fforest y Ddena

Name:  Cymin

OS 1:50,000 map:  162

Summit Grid Reference:  SO 52771 12511 (LIDAR)

Summit Height:  256.4m (LIDAR)

Bwlch Grid Reference:  SO 53644 12441 (LIDAR)

Drop Summit to Bwlch:  85.8m (LIDAR)

Drop Bwlch to ODN:  170.6m (LIDAR)

Dominance:  33.47% (LIDAR)

Myrddyn Phillips (April 2020)

Mapping Mountains – Hill Reclassifications – Y Trechol – The Dominant Hills of Wales

THIS HILL HAS SUBSEQUENTLY BEEN REINSTATED AS A LESSER DOMINANT

Cymin (SO 527 125) – Lesser Dominant deletion

There has been a deletion to the listing of 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 detail on contemporary Ordnance Survey maps.

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

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 3^rd 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 Cymin and it is adjoined to the Fforest y Ddena 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 A4136 road to its north and the A466 road to its south-west, and has the town of Trefynwy (Monmouth) towards the west.

When the original 200m height band of Welsh P30 hills published on Geoff Crowder’s v-g.me website were standardised and interpolated heights also included, this hill was listed with c 86m of drop and 33.46% dominance, based on an estimated c 257m summit height and an estimated c 171m bwlch height, with these heights estimated from interpolation of 5m contouring that appears on the Ordnance Survey 1:25,000 Outdoor Leisure (latterly Explorer) map.

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 256m spot height on the area of this hill’s summit positioned at SO 527 125, and when coupled with the estimated c 171m bwlch height, these values give this hill c 85m of drop and 33.20% dominance.  The 256m spot height is also shown on Ordnance Survey data that appears on the Magic Maps website.

Extract from the Magic Maps website

Therefore, the deletion of this hill from Lesser Dominant status is due to detail on contemporary Ordnance Survey maps, resulting in a 256m summit height and an estimated c 171m bwlch height, with these values giving this hill an estimated c 85m of drop and 33.20% dominance, which is insufficient for this hill’s continued classification as a Lesser Dominant.

The full details for the hill are:

Group:  Fforest y Ddena

Name:  Cymin

OS 1:50,000 map:  162

Summit Grid Reference:  SO 52762 12507 (spot height)

Summit Height:  256m (spot height)

Bwlch Grid Reference:  SO 53657 12428 (interpolation)

Drop Summit to Bwlch:  c 85m (spot height summit and interpolated bwlch)

Drop Bwlch to ODN:  c 171m (interpolation)

Dominance:  33.20% (spot height summit and interpolated bwlch)

Myrddyn Phillips (April 2020)

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

Cymin (SO 527 125)

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, their locations, the drop, dominance and status of the hill confirmed by LIDAR analysis conducted by Myrddyn Phillips.

LIDAR image of Cymin (SO 527 125)

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 with 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.

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, with the Introduction to the Mapping Mountains publication of this list appearing on the 3^rd December 2015, and which is now available in its entirety on Mapping Mountains in Google Doc format.

The hill is adjoined to the Fforest y Ddena 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 A4136 road to its north and the A466 road to its south-west, and has the town of Trefynwy (Monmouth) towards the west.

The hill appeared in the original 200m Welsh P30 list on Geoff Crowder’s v-g.me website under the name of Kymin Tower, which is a name that appeared near the summit of this hill on Ordnance Survey 1:25,000 Outdoor Leisure maps of the day.

Kymin Tower

250c

SO528124

162

14

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.  The name of Kymin Tower refers to an 18^th century round house and naval temple that are positioned on the summit area of this hill, as these are inanimate objects a name that refers directly to the hill is more appropriate.

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

Contemporary Ordnance Survey maps use the name Kymin which is positioned near the summit of this hill.  This form of this name also appears in a number of online sources.  The word Kymin is anglicised from the Welsh word Cymin, meaning common or unenclosed land, with the definite article ‘Y’ lost as evidenced in the anglicised form (Place-names of Gwent, Richard Morgan, Gwasg Carreg Gwalch 2005).

The intricacies of language and prioritising one in favour of another for listing a hill is fraught with complication, with originating Cymraeg names being anglicised and also originating English names being cymricised, examples such as these are more common in border country and especially so for anglicised forms.  There is no steadfast rule that fits all, but as a standard a name that has its origins in the Welsh language and where this is substantiated by either historic documentation and / or contemporary usage should be prioritised in favour of a contemporary anglicised or English version of the name.  Likewise, if a name exists where an element of it is in English and if this name applies to a hill that is situated in a Welsh speaking part of Wales it is standard practice to use a full Welsh term for the name.  It is also standard practice to use a Welsh name for a hill if another name exists that has originated in a different language.

Therefore, the name this hill is now listed by in the 200m Twmpau and Y Trechol – The Dominant Hills of Wales is Cymin, and this was derived from the anglicised form that appears on contemporary Ordnance Survey maps. 

The full details for the hill are:

Group:  Fforest y Ddena

Name:  Cymin

Previously Listed Name:  Kymin Tower

OS 1:50,000 map:  162

Summit Height:  256.4m (LIDAR)

Summit Grid Reference:  SO 52771 12511 (LIDAR)

Bwlch Height:  170.6m (LIDAR)

Bwlch Grid Reference:  SO 53644 12441 (LIDAR)

 

Drop:  85.8m (LIDAR)

Dominance:  33.47% (LIDAR)

Myrddyn Phillips (April 2020)