Mapping Mountains – Significant Name Changes – Y Pedwarau - The 400m Hills of Wales

Pen Crwn (SN 963 736)

There has been a Significant Name Change to a hill that is listed in the Y Pedwarau, with the hill's height and drop being confirmed by a survey with the Trimble GeoXH 6000 which took place on the 12^th March 2016.

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

Y Pedwarau - These are the Welsh hills at and above 400m and below 500m in height that have 30m minimum drop.  The list is co-authored by Myrddyn Phillips and Aled Williams, with the introduction to the Mapping Mountains publication of this list appearing on the 30th January 2017.

The hill is a part of the Pegwn Mawr range, this group of hills is situated in the north-eastern part of Mid and West Wales, and the hill is positioned to the south-west of the small community of Pant-y-dŵr and to the north of Rhaeadr Gwy (Rhayader).

The Trimble GeoXH 6000 gathering data at the summit of Pen Crwn

The hill appeared in the 400m P30 list on Geoff Crowder’s v-g.me website under the name of Cefn Lletyhywel, which is a name that appeared close to the summit of the hill on Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps of the day.  

Cefn Lletyhywel

487m

SN963736

136/147

214

  

During my early hill listing I paid little regard to name placement on a 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 inappropriate, and Cefn Lletyhywel is such an example as this name has been consistently applied by the Ordnance Survey to land below and to the south of the summit of this hill, whilst a number of different scaled Ordnance Survey maps position the name Pen Crwn as applicable to land taking in the summit of this hill.  

Extract from the Ordnance Survey series of Six-Inch maps

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

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

Therefore, the name this hill is now listed by in the Y Pedwarau is Pen Crwn and this was derived from a number of different scaled Ordnance Survey maps that place this name applicable to land that takes in the summit of this hill.

The full details for the hill are:

Group:  Pegwn Mawr

Name:  Pen Crwn

Previously Listed Name:  Cefn Lletyhywel 

Summit Height:  486.7m (converted to OSGM15)

OS 1:50,000 map:  136, 147

Summit Grid Reference:  SN 96320 73629

 

Drop:  52.0m (converted to OSGM15)

For details on the survey of Pen Crwn

Myrddyn Phillips and Aled Williams (October 2016)