Mapping Mountains – Significant Name Changes – 100m Twmpau

 

Pt. 185.9m (SO 181 991) 

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 confirmed by LIDAR analysis and a subsequent Trimble GeoXH 6000 survey conducted by Myrddyn Phillips. 

LIDAR image of Pt. 185.9m (SO 181 991)

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. 

The 100m Twmpau by Myrddyn Phillips

The hill is adjoined to the Carnedd Wen group of hills which are situated in the south-eastern part of North Wales (Region A, Sub-Region A4), and it has a minor road to its south-west and the A483 road to its south-east, and has the village of Aberriw (Berriew) towards the north north-east. 

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

The hill originally appeared in the 100m P30 list on Geoff Crowder’s v-g.me website under a partly transposed and invented name of Bryn y Garthmyl, with an accompanying note stating; Name from surrounding district.

Bryn y Garthmyl

186m

SO182992

136

216

Name from surrounding district

 

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 small community and add the words Bryn y 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. 

The Trimble GeoXH 6000 gathering data at the summit of Pt. 185.9m (SO 181 991)

However, occasionally even when research is conducted an appropriate name for the hill may not be found, and on such occasions the listing protocol is to use the point (Pt. 185.9m) notation, and in the case of this hill, this is such an example. 

Therefore, the name this hill is now listed by in the 100m Twmpau is Pt. 185.9m, and this is being used as the author has not found an appropriate name for it either through historic research and / or local enquiry. 

 

The full details for the hill are: 

Group:  Carnedd Wen 

Name:  Pt. 185.9m

Previously Listed Name:  Bryn y Garthmyl 

OS 1:50,000 map:  136

Summit Height:  185.9m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SO 18181 99192 (Trimble GeoXH 6000)

Bwlch Height:  131.5m (LIDAR)

Bwlch Grid Reference:  SO 16899 99363 (LIDAR) 

Drop:  54.4m (Trimble GeoXH 6000 summit and LIDAR bwlch)

 

Myrddyn Phillips (March 2021)