Mapping Mountains – Hill Reclassifications – 30-99m Twmpau

 

Mynydd Penygarreg (SH 815 818) – 30-99m Sub-Twmpau addition 

There has been confirmation of an addition to the list of 30-99m 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 Mynydd Penygarreg (SH 815 818)

The criteria for the list that this addition applies to are:

30-99m Twmpau – Welsh hills at or above 30m and below 100m in height that have 30m minimum drop, with an accompanying sub list entitled the 30-99m Sub-Twmpau, with the criteria for this sub category being all Welsh hills at or above 30m and below 100m 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. 

30-99m Twmpau by Myrddyn Phillips

The name the hill is listed by is Mynydd Penygarreg, and it is adjoined to the Mynydd Hiraethog group of hills, which are situated in the northern part of North Wales (Region A, Sub-Region A2), and it is positioned with the B5115 road to its immediate south-west, and has the town of Llandudno towards the west.

When the original 30-99m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was not included in the Hills to be surveyed sub list, as it was considered not to meet the criteria then used for this sub category.

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 21m of drop, based on an estimated c 83m summit height and an estimated c 62m bwlch height, with both heights based on interpolation of 5m contouring. 

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

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 confirmation of the addition of this hill to 30-99m Sub-Twmpau status is due to LIDAR analysis, resulting in an 83.9m summit height and a 61.6m bwlch height, with these values giving this hill 22.4m of drop, which is sufficient for it to be classified as a 30-99m Sub-Twmpau. 

 

The full details for the hill are: 

Group:  Mynydd Hiraethog 

Name:  Mynydd Penygarreg 

OS 1:50,000 map:  116

Summit Height:  83.9m (LIDAR) 

Summit Grid Reference:  SH 81597 81831 (LIDAR)               

Bwlch Height:  61.6m (LIDAR) 

Bwlch Grid Reference:  SH 81599 81981 (LIDAR) 

Drop:  22.4m (LIDAR) 

 

Myrddyn Phillips (July 2024)

 

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

 

Mynydd Aberysgir (SN 981 323) 

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 LIDAR analysis conducted by Myrddyn Phillips. 

LIDAR image of Mynydd Aberysgir (SN 981 323)

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 Mynydd Epynt group of hills, which are situated in the central part of South Wales (Region B, Sub-Region B1), and it is positioned encircled by minor roads, with the A40 road farther to its south, and has the town of Aberhonddu (Brecon) towards the south-east.

The hill appeared in the original 300m height band of Welsh P30 hills published on Geoff Crowder’s v-g.me website, under the invented and transposed name of Mynydd Aberbiran, with an accompanying note stating; Name from stream to the South-West.

Mynydd Aberbiran

377m

SN982323

160

12

Trig pillar. Name from stream 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 or as in this instance transpose the name of a stream and add the word Mynydd 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 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 along with the contemporary Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and the Tithe map that has instigated the change in the listed name of this hill.

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 places the name Mynydd Aber Esgair close to its summit. 

Extract from the Ordnance Survey Draft Surveyors 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 20 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 Aberysgir Common in the apportionments, with the details on the Tithe map appearing in the parish of Aberysgir and in the county named as Brecon. 

Extract from the apportionments

Therefore, the name this hill is now listed by in the Y Trichant – The 300m Hills of Wales is Mynydd Aberysgir and this was derived from the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map in combination with the Ordnance Survey Draft Surveyors map and the Tithe map. 

 

The full details for the hill are: 

Group:  Mynydd Epynt 

Name:  Mynydd Aberysgir 

Previously Listed Name:  Mynydd Aberbiran 

OS 1:50,000 map:  160

Summit Height:  376.9m (LIDAR)                                                           

Summit Grid Reference:  SN 98148 32329 (LIDAR) 

Bwlch Height:  322.9m (LIDAR) 

Bwlch Grid Reference:  SN 97687 33562 (LIDAR) 

Drop:  54.0m (LIDAR) 

 

Myrddyn Phillips (July 2024)