Monday 22 April 2024

Mapping Mountains – Significant Name Changes – 30-99m Twmpau

 

Carreg Waring (SH 537 390) 

There has been a Significant Name Change to a hill that is listed in the 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 Carreg Waring (SH 537 390)

The criteria for the list that this name change 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 hill is adjoined to the Moel Hebog group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the A497 road to its north and a minor road to its east, and has the town of Porthmadog towards the east.

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 under the point (Pt. 57m) notation with an estimated c 23m of drop, based on the 57m summit spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map and an estimated c 34m bwlch height, based on interpolation of 5m contouring between 30m – 35m. 

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.

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 name the area of land taking in the summit of this hill as Rabbit Warren.

Extract from the Ordnance Survey series of Six-Inch maps

This name was subsequently queried with Aled Williams, who is local to the area where this hill is situated.  Aled informed me that the hill is known locally as Carreg Waring, with the latter word being equivalent to a rabbit warren.

Therefore, the name this hill is now listed by in the 30-99m Twmpau is Carreg Waring, and this was derived by a combination of the Ordnance Survey series of Six-Inch maps and local enquiry. 

 

The full details for the hill are:

Group:  Moel Hebog

Name:  Carreg Waring

Previously Listed Name:  Pt. 57m 

OS 1:50,000 map:  124

Summit Height:  57.15m (LIDAR) 

Summit Grid Reference:  SH 53734 39025 (LIDAR)               

Bwlch Height:  33.0m (LIDAR) 

Bwlch Grid Reference:  SH 53892 38892 (LIDAR) 

Drop:  24.1m (LIDAR) 

 

My thanks to Aled Williams for advice relating to the listed name of this hill. 

Myrddyn Phillips (April 2024)

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