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

Pt. 428.9m (SO 035 449) 

There has been a Significant Name Change with the details being retrospective to a hill that is listed in the Y Pedwarau – The 400m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill derived from a Trimble GeoXH 6000 summit survey and LIDAR bwlch analysis conducted by Myrddyn Phillips and Aled Williams. 

Pt. 428.9m (SO 035 449)

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

Y Pedwarau – The 400m Hills of Wales.  Welsh hills at or above 400m and below 500m in height that have 30m minimum drop, accompanying the main list are five categories of sub hills; 500m Sub-Pedwarau, 500m Double Sub-Pedwarau, 400m Sub-Pedwarau, 390m Sub-Pedwarau and the 390m Double Sub-Pedwarau.  The list is co-authored by Myrddyn Phillips and Aled Williams and is published on Mapping Mountains in Google Doc format.

Y Pedwarau - The 400m Hills of Wales by Myrddyn Phillips and Aled Williams

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 with a minor road to its north and south-east, and the B4520 road to its west, and has the town of Llanfair-ym-Muallt (Builth Wells) towards the north.

The hill appeared in the original Welsh 400m P30 list compiled by Myrddyn Phillips and published on Geoff Crowder’s v-g.me website, under the directional name of Banc y Celyn South-West Top, with an accompanying note stating; Name from hill to the North-East.

Banc y Celyn South-West Top

430c

SO035450

147/160

188

Name from hill to the North-East

When Myrddyn Phillips first compiled this list he 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.  His 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 he now advocates 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 1:50,000 Landranger map

However, on occasion even when research is conducted an appropriate name for the hill may not be found, and on such occasions the listing protocol is to use the point notation, and this is the protocol adopted when Myrddyn Phillips and Aled Williams became co-authors of this list and the 1^st edition of the Y Pedwarau was published by Europeaklist in May 2013.  This hill was then listed under the point (Pt. c 430m) notation with an estimated c 33m of drop, based on interpolation of the small uppermost 430m summit ring contour that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and an estimated c 397m bwlch height, based on interpolation of 10m contouring between 390m – 400m. 

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

Therefore, the name this hill is now listed by in the Y Pedwarau – The 400m Hills of Wales is Pt. 428.9m, and this is being used as the authors have not found an appropriate name for the hill either through historic research and/or local enquiry. 

 

The full details for the hill are: 

Group:  Mynydd Epynt 

Name:  Pt. 428.9m 

Previously Listed Name:  Banc y Celyn South-West Top 

OS 1:50,000 map:  147, 160 

Summit Height:  428.9m (converted to OSGM15, Trimble GeoXH 6000) 

Summit Grid Reference:  SO 03592 44968 (Trimble GeoXH 6000) 

Bwlch Height:  396.7m (LIDAR) 

Bwlch Grid Reference:  SO 03648 45409 & SO 03664 45405 (LIDAR) 

Drop:  32.1m (Trimble GeoXH 6000 summit and LIDAR bwlch) 

 

Myrddyn Phillips and Aled Williams (March 2025)