Mapping Mountains – Significant Name Changes – 100m Twmpau and Y Trechol – The Dominant Hills of Wales

Cae Ddu Main (SN 622 983)

There has been a Significant Name Change to a hill that is listed in the 100m Twmpau and Y Trechol – The Dominant Hills of Wales, with the summit height, its location, the drop and status of the hill confirmed by LIDAR analysis conducted by Myrddyn Phillips.

LIDAR image of Cae Ddu Main

The criteria for the two lists 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.

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.

The hill is adjoined to the Mynydd Penlle’rcastell group of hills, which are situated in the western part of South Wales (Region C, Sub-Region C1), and is positioned with the A483 road to its immediate west and the A48 and M4 to its north, and has the village of Penlle’r-gaer to its north.

The hill originally appeared in the 100m P30 list on Geoff Crowder’s v-g.me website under the invented name of Valley Wood Hill, with an accompanying note stating; Name from wood to the North-East.

Valley Wood Hill

102m

SS619984

159

164/165/178

Name from wood to the North-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 use the name of a wood and add the word Hill 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 beside a raised field boundary, with land either side of this considered of equal height, and the prioritised summit position is given the number 2928 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 ddu main in the apportionments, with the details on the Tithe map appearing in the parish of Llangyfelach and in the county named as Glamorgan.

Extract from the apportionments

Therefore, the name this hill is now listed by in the 100m Twmpau and Y Trehol – The Dominant Hills of Wales is Cae Ddu Main, and this name was derived from the Tithe map.

The full details for the hill are:

Group:  Mynydd Penlle’rcastell

Name:  Cae Ddu Main

Previously Listed Name:  Valley Wood Hill

  

OS 1:50,000 map:  159

Summit Height:  106.9m (LIDAR, remaining natural high point)

Summit Grid Reference:  SN 62212 98337 (LIDAR, remaining natural high point)

Bwlch Height:  69.1m (LIDAR, natural bwlch)

Bwlch Grid Reference:  SN 62051 00000 (LIDAR, natural bwlch) 

Drop:  37.8m (LIDAR)

Dominance:  35.34% (LIDAR)

Myrddyn Phillips (February 2019)