Mapping Mountains – Summit Relocations – 100m Twmpau

 

Cae (SN 560 038) 

There has been a Summit Relocation 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 Cae (SN 560 038)

The criteria for the list that this summit relocation 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.  The list is authored by Myrddyn Phillips, 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 between the stream valleys of the Afon Morlais to its west and the Afon Gwili to its east, and has the towns of Llanelli to the south-west and Pontarddulais to 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 included in the main P30 list with a 119m summit height, based on the spot height that appears at SN 56057 03826 on the contemporary Ordnance Survey 1:25,000 Explorer map. 

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-assessed and it was listed with an estimated c 39m of drop, based on the 118m 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 79m bwlch height, based on interpolation of 5m contouring between 75m – 80m.

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 119.9m positioned at SN 56063 03818.  However, this is to the top of a raised field 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 Cae (SN 560 038)

The height produced by LIDAR analysis to the natural summit of this hill is 119.0m and is positioned at SN 56069 03819, 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 judged to be 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 height produced by LIDAR analysis to the natural summit of this hill is 119.0m and is positioned at SN 56069 03819, this is relatively close to where the spot height appears, and is approximately six metres eastward from the high point of the raised field boundary. 

 

The full details for the hill are: 

Group:  Mynydd Sylen 

Name:  Cae 

OS 1:50,000 map:  159

Summit Height:  119.0m (LIDAR)               

Summit Grid Reference (New Position):  SN 56069 03819 (LIDAR) 

Bwlch Height:  80.0m (LIDAR) 

Bwlch Grid Reference:  SN 55961 04021 (LIDAR) 

Drop:  39.0m (LIDAR) 

 

Myrddyn Phillips (December 2024)

 

 

  

Mapping Mountains – Significant Name Changes – 100m Twmpau

Cae (SN 560 038)

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 Cae (SN 560 038)

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 with 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 Myrddy 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 is positioned between the stream valleys of the Afon Morlais to its west and the Afon Gwili to its east, and has the towns of Llanelli to the south-west and Pontarddulais to the east.

The hill appeared in the original 100m height band of Welsh P30 hills published on Geoff Crowder’s v-g.me website, under the invented and transposed name of Bryn Tyreglwys, with an accompanying note stating; Name from farm to the South-West.

Bryn Tyreglwys

119m

SN561038

159

164/178

Name from farm to the South-West

  

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.  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 105 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 Cae 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 Cae, and this was derived from the Tithe map.

The full details for the hill are:

Group:  Mynydd Sylen

Name:  Cae

Previously Listed Name:  Bryn Tyreglwys 

OS 1:50,000 map:  159

Summit Height:  119.0m (LIDAR)

Summit Grid Reference:  SN 56069 03819 (LIDAR)

Bwlch Height:  80.0m (LIDAR)

Bwlch Grid Reference:  SN 55961 04021 (LIDAR)

  

Drop:  39.0m (LIDAR)

Myrddyn Phillips (November 2018)

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

Cae (SN 560 038) – Lesser Dominant deletion

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, dominance and status of the hill derived from LIDAR analysis conducted by Myrddyn Phillips.

LIDAR image of Cae (SN 560 038)

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. 

Y Trechol - The Dominant Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Cae and this was derived from the Tithe map, and it 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 is positioned between the stream valleys of the Afon Morlais to its west and the Afon Gwili to its east, and has the towns of Llanelli to the south-west and Pontarddulais to 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 included in the main P30 list with a 119m summit height, based on the spot height that appears on the contemporary Ordnance Survey 1:25,000 Explorer map. 

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 with an estimated c 40m of drop, based on the 119m summit spot height and an estimated c 79m bwlch height, based on interpolation of 5m contouring between 75m – 80m, resulting in a dominance value of 33.61%, which was sufficient for Lesser Dominant status.

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 deletion of this hill from Lesser Dominant status is due to LIDAR analysis, resulting in a 119.0m summit height and an 80.0m bwlch height, with these values giving this hill 39.0m drop and 32.79% dominance, which is insufficient for Lesser Dominant status.

The full details for the hill are:

Group:  Mynydd Sylen

Name:  Cae

OS 1:50,000 map:  159

Summit Height:  119.0m (LIDAR)

Summit Grid Reference:  SN 56069 03819 (LIDAR)

Bwlch Height:  80.0m (LIDAR)

Bwlch Grid Reference:  SN 55961 04021 (LIDAR)

  

Drop:  39.0m (LIDAR)

Dominance:  32.79% (LIDAR)

Myrddyn Phillips (November 2018)