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

Cnwc yr Hydd (SN 082 344) 

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 Cnwc yr Hydd (SN 082 344)

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 Preseli group of hills, which are situated in the south-western part of South Wales (Region B, Sub-Region B1), and it is positioned with minor roads to its east, north and west, and the B4329 road farther to its south-east, and has the town of Trefdraeth (Newport) towards the north 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 transposed name of Waun Mawr, with an accompanying note stating; aka Cnwc yr Hydd.

Waun Mawr

339m

SN083344

145

35

aka Cnwc yr Hydd

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, with little consideration for the meaning of the name used and where it was appropriately applied to.  My preference was to use farm names and put Pen, Bryn or Moel in front of them or as in this instance transpose a prominent name that appears just to the south of the summit on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map.  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 series of Ordnance Survey Six-Inch maps that form the basis of the change in the listed name of this hill. 

Extract from the Ordnance Survey series of Six-Inch maps

The Ordnance Survey series of Six-Inch 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 place the name of Cnwc yr Hydd adjacent to the summit of this hill with the name of Waun Mawr applied to a feature of the hill to the south.

Therefore, the name this hill is now listed by in the Y Trichant – The 300m Hills of Wales is Cnwc yr Hydd and this was derived from the contemporary Ordnance Survey 1:25,000 Explorer map and confirmed by the Ordnance Survey series of Six-Inch maps. 

 

The full details for the hill are: 

Group:  Mynydd Preseli 

Name:  Cnwc yr Hydd 

Previously Listed Name:  Waun Mawr 

OS 1:50,000 map:  145

Summit Height:  339.1m (LIDAR)                                                           

Summit Grid Reference:  SN 08290 34475 (LIDAR) 

Bwlch Height:  291.7m (LIDAR) 

Bwlch Grid Reference:  SN 08175 33624 (LIDAR) 

Drop:  47.4m (LIDAR) 

 

Myrddyn Phillips (October 2024)