Mapping Mountains – Significant Name Changes – Y Trichant and Y Trechol – The Dominant Hills of Wales

Mynydd Penlle’rcastell (SN 664 095)

There has been a Significant Name Change to a hill that is listed in the Y Trichant and Y Trechol – The Dominant Hills of Wales, with the summit height, its location and drop 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 1^st August 2018.

Mynydd Penlle'rcastell (SN 664 095)

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

Y Trichant – 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 its renaming appearing on Mapping Mountains on the 13^th May 2017.

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, with the Introduction to the Mapping Mountains publication of this list appearing on the 3^rd December 2015.

LIDAR image of Mynydd Penlle'rcastell

The hill is the highest in its own group, therefore it is adjoined to the Mynydd Penlle’rcastell range of hills which are situated in the western part of South Wales (Region C, Sub-Region C1), and it is positioned with the Afon Llwchwr (River Loughor) to its west and the A 474 to its north and east, and has the town of Rhydaman (Ammanford) to its north-west.

The hill appeared in the original Welsh P30 lists under the 300m height band on Geoff Crowder’s v-g.me website, under the name of Mynydd y Betws, which is a name consistently applied to the northern part of this hill on Ordnance Survey maps.

Mynydd y Betws

371m

SN665094

159

165/178

Marilyn. Clem/Yeaman. 374m on 1987 1:50000 map. Trig pillar at 339m to the North-West.

 

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.

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

There are three names that are consistently applied to the upper part of this hill on Ordnance Survey maps, these are:

Mynydd y Betws, which appears on the northern part of the hill.

Penlle’rcastell, which appears close to its summit.

Mynydd y Gwair, which appears on the southern part of the hill.

Having these three names consistently appearing on Ordnance Survey maps for the upper part of this hill indicates that there is a boundary between where these names are applicable to.  Therefore, the Tithe map was consulted.

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.  However, in this instance the upper part of this hill is open and it is named Mynydd Penlle’rcastell on the Tithe map.

Extract from the Tithe map

Therefore, the name this hill is now listed by in the Y Trichant and Y Trechol – The Dominant Hills of Wales is Mynydd Penlle’rcastell, and this name was derived from the Tithe map.

The full details for the hill are:

Group:  Mynydd Penlle’rcastell

Name:  Mynydd Penlle’rcastell

Previously Listed Name:  Mynydd y Betws

OS 1:50,000 map:  159

Summit Height:  373.3m (converted to OSGM15)

Summit Grid Reference:  SN 66498 09531

Bwlch Height:  166.4m (LIDAR)

Bwlch Grid Reference:  SN 69945 09589 (LIDAR)

Drop:  206.9m (Trimble summit and LIDAR bwlch)

Dominance:  55.42% (Trimble summit and LIDAR bwlch)

For details on the summit survey of Mynydd Penlle’rcastell

Myrddyn Phillips (January 2019)

Mapping Mountains – Trimble Surveys – Mynydd Penlle’rcastell

01.08.18  Mynydd Penlle’rcastell (SN 664 095)

Mynydd Penlle'rcastell (SN 664 095)

The ruins of Penlle’rcastell stand atop a flattened mound of a hill overlooking the Afon Aman (River Amman) to its north; nowadays the whole hill is encircled by roads with the A474 following the course of this river hereabouts and the M4 toward the south, with a number of towns also encircling the hill, including Rhydaman (Ammanford), Pontarddulais, Pontardawe and Glanaman.

The old fortification atop the hill is thought to date from the late 13^th century and is associated with the Marcher Lords, today its earthwork system of ditches and embankments is still impressive, but where once its view would be unencumbered, today one looks out on the Mynydd y Betws Wind Farm which incorporates 15 turbines that are 110m (361ft) in height.

I’d often wondered what name would be most appropriate for this hill as those of Mynydd y Betws and Mynydd y Gwair have been presented on Ordnance Survey maps, with the position of the former consistently given on the upper northern part of the hill, and the latter on the upper southern part of the hill.  However, it is the Tithe map that delineates the land boundary of each and also names the central land taking in the summit of this hill as Mynydd Penlle’rcastell.

Today I was out on a bagging road trip with Suzanne, a good friend for many a year and who was house sitting for one of her friends in Caerfyrddin (Carmarthen) for the week.  If wanting easy access to the summit of Mynydd Penlle’rcastell a minor road crosses the hill in a north to south direction and at its high point there is sufficient space to park one or two cars, and with six hills planned for the day we opted for this easy access route.

Whilst heading east driving toward the hill dark shower clouds hung over it, and although the westerly breeze pushed these forever inland a darkened sky met us when we pulled up at the top of the minor road crossing the hill.

A narrow path led across the grassland toward the earthworks of Penlle’rcastell and this passed within a few metres of where LIDAR analysis places two points that vie for the summit position of this hill, and as Suzanne headed toward the ditches and embankments I used the Trimble as a hand-held device and zeroed in to the first of these two positions.

LIDAR image of the summit of Mynydd Penlle'rcastell

Suzanne heading toward the remains of Penlle'rcastell

Once the Trimble was gathering data I joined my bagging accomplice and investigated the ruined fortification.  During this an occasional light shower sped across the hill with the rain no more than spots brought on the breeze, and with a brightening forecast for late morning and afternoon it looked as if our timing on this hill was perfect.

Gathering data at one of two points surveyed for the summit position of Mynydd Penlle'rcastell

With one data set gathered and stored I positioned the Trimble at the second point that LIDAR indicates for the high point of this hill and gathered another data set.  Once data were stored I packed the equipment away and we turned toward my car and walked the short distance back to the minor road, next stop; Mynydd Sylen (SN 515 080).

Survey Result:

Mynydd Penlle’rcastell (significant name change)

Summit Height:  373.3m (converted to OSGM15)

Summit Grid Reference:  SN 66498 09531

Bwlch Height:  166.4m (LIDAR)

Bwlch Grid Reference:  SN 69945 09589 (LIDAR)

Drop:  206.9m

Dominance:  55.42%

For further details please consult the Trimble Survey Spreadsheet