Mapping Mountains – Significant Name Changes – 200m Twmpau

Banc Pontfaen (SN 564 484) 

There has been a Significant Name Change to a hill that is listed in the 200m 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 Banc Pontfaen (SN 564 484)

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

200m Twmpau – Welsh hills at or above 200m and below 300m in height that have 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. 

The 200m Twmpau by Myrddyn Phillips

The hill is adjoined to the Mynydd Bach group of hills, which are situated in the western part of South Wales (Region B, Sub-Region B1), and it is positioned with the A482 road to its north-east, and a minor road to its south-west and east, and has the town of Llanbedr Pont Steffan (Lampeter) towards the east south-east.

The qualifying hill appeared in the original Welsh 200m P30 list on Geoff Crowder’s v-g.me website, under the invented and transposed name of Allt Ty-llwyd, with an accompanying note stating; Name from buildings to the South-East.

Allt Ty-llwyd

224m

SN550487

146

199

Name from buildings to the South-East.

 

When the sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-evaluated and its summit relocated to SN 564 484 and listed under the name of Blaen-wern Wood with an estimated c 32m of drop, based on an estimated c 226m summit height and an estimated c 194m bwlch height, with both heights based on interpolation of 5m contouring that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map. 

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

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.  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.

Since the original publication of the Welsh P30 lists on Geoff Crowder’s v-g.me website there have been a number of maps made available online.  Some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map, whilst others are current and digitally updated such as the interactive mapping on the Magic Maps and WalkLakes websites.  One of the historic maps now available online is the Ordnance Survey Draft Surveyors map which formed the basis for the first publicly available Ordnance Survey One-Inch ‘Old Series’ map, and it is the Draft Surveyors map that has prompted the change in the listed name of this hill. 

Extract from the Ordnance Survey Draft Surveyors Map

The Draft Surveyors maps consist of the preliminary drawings made by the Ordnance Survey surveyors between the 1780s and 1840 and formed the basis for the first publicly available One-Inch map.  They were drawn at scales of six inches to the mile for areas considered of particular military significance and down to two inches to the mile for other areas.  Fair copies were then produced from these preliminary drawings to one inch to the mile and then copper plates were prepared for printing.  The Draft Surveyors maps for the whole of Wales are now available online and they form an important part in the study of Welsh upland place-names as they bridge the time frame between the late 18^th century and the mid-19^th century when the Ordnance Survey produced their first One-Inch maps, and importantly for this hill and its listed name, it is this map that uses the name of Pontfaen Bank, with it being listed as Banc Pontfaen 

Therefore, the name this hill is now listed by in the 200m Twmpau is Banc Pontfaen, and this was derived from the Ordnance Survey Draft Surveyors Map. 

 

The full details for the hill are:

Group:  Mynydd Bach

Name:  Banc Pontfaen

Previously Listed Name:  Blaen-wern Wood   

OS 1:50,000 map:  146

Summit Height:  225.6m (LIDAR) 

Summit Grid Reference:  SN 56441 48477 (LIDAR) 

Bwlch Height:  194.2m (LIDAR) 

Bwlch Grid Reference:  SN 55294 49452 (LIDAR) 

Drop:  31.4m (LIDAR) 

 

Myrddyn Phillips (December 2022)