Mapping Mountains – Significant Name Changes – Y Trichant – The 300m Hills of Wales

Allt Bryn Teg (SN 684 440) 

There has been a Significant Name Change to a hill that is listed in the Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill derived from detail on contemporary maps produced from Ordnance Survey data. 

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

Y Trichant – The 300m Hills of Wales – 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 the renaming of it appearing on Mapping Mountains on the 13^th May 2017, and the Introduction to the Mapping Mountains publication of the list appearing on the 1^st January 2022. 

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

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

The hill appeared in the original 300m height band of Welsh P30 hills published on Geoff Crowder’s v-g.me website, under the directional name of Allt yr Hebog South-west Top, with an accompanying note stating; Name from hill to the North-East.

Allt yr Hebog South-West Top

330c

SN684441

146

187/199

Name from hill 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 a directional name based on supplanting the name of a near hill and adding a directional component 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

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, and it is the positioning of the spot height and the name placement on the series of Ordnance Survey Six-Inch maps that form the basis of the change in the listed name of this hill.

One of the mapping resources now available online is the WalkLakes website which hosts an interactive map originated from the Ordnance Survey Open Data programme.  This map has many spot heights not on other publicly available maps and a 331m summit spot height appears on this map for this hill. 

Extract from the interactive mapping hosted on the WalkLakes website

Another resource now available online is the interactive mapping hosted on the Welsh Government website and entitled the DataMapWales.  This mapping has 5m contours and its detail matches that produced from the OS Terrain 5 product, which compliments much of that produced from LIDAR.  This map also has a 331m summit height with its placement indicates it is on land known as Allt Bryn Teg. 

Extract from the interactive mapping entitled the DataMapWales

However, for confirmation of name placement the Ordnance Survey series of Six-Inch maps were consulted.  These maps formed the base map Ordnance Survey used for many decades leading to the production of the 1:10,000 Series of maps, both have now been superseded by the digitised Master Map.  The series of Six-Inch maps are excellent for name placement and especially so compared to the contemporary Ordnance Survey 1:25,000 Explorer map, and it is the series of Six-Inch maps that give the land incorporating the summit of this hill as a part of Allt Bryn Teg.

Extract from the Ordnance Survey series of Six-Inch maps

Therefore, the name this hill is now listed by in the Y Trichant – The 300m Hills of Wales is Allt Bryn Teg and this was derived from the position of the summit spot height being on the land of Allt Bryn Teg. 

 

The full details for the hill are: 

Group:  Esgair Wen 

Name:  Allt Bryn Teg 

Previously Listed Name:  Allt yr Hebog South-west Top 

OS 1:50,000 map:  146

Summit Height:  331m (spot height)                                                           

Summit Grid Reference:  SN 68400 44000 (spot height) 

Bwlch Height:  c 308m (interpolation) 

Bwlch Grid Reference:  SN 68478 44305 (interpolation) 

Drop:  c 23m (spot height summit and interpolated bwlch) 

 

Myrddyn Phillips (May 2023)