Sunday, 14 May 2017

Mapping Mountains – Hill Reclassifications – Y Pedwarau


Fainc Fawr (SN 741 893) – Pedwar reclassified to 400m Sub-Pedwar

There has been a reclassification to the listing of Y Pedwarau with a Pedwar being reclassified to a 400m Sub-Pedwar due to analysis of LIDAR data by Aled Williams.  Y Pedwarau is the title for the list of 400m hills of Wales and takes in all Welsh hills at or above 400m and below 500m in height that have a minimum 30m of drop, the list is a joint compilation between Myrddyn Phillips and Aled Williams and it commenced publication on Mapping Mountains on the 30.01.17.

Accompanying the main Y Pedwarau list are five categories of sub hills, with this reclassification affecting the 400m Sub-Pedwar category.  The criteria for 400m Sub-Pedwar qualification is all Welsh hills at or above 400m and below 500m in height with 20m or more and below 30m of drop.

Prior to analysis of LIDAR data the hill was listed with 32m of drop based on a basic levelling survey (BLS) conducted by Myrddyn Phillips on the 17.04.03, with the resulting 104ft (31.7m) of drop being sufficient for the hill to be listed in the main P30 list.  With a 467m summit spot height on the Ordnance Survey 1:25,000 Explorer map this BLS places the height of the bwlch at 435m.  The hill was duly listed under the name Bryniau Rhyddion, please note; the name this hill is now listed by is Fainc Fawr.

The hill is situated in the Pumlumon group of hills with its Cardinal Hill being Banc Llechwedd Mawr (SN 775 898) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B2), and is positioned with the small community of Tal-y-bont to its west and Ponterwyd to its south.

Access to the hill is relatively easy from the south-west as a public footpath heads east on a track from a minor road before leaving the track and following the course of a stream toward the north.  As the whole of this hill is a part of designated open access land the broad southern ridge of the hill can be followed to its summit from the public footpath and track to the south.

The name of the hill is Fainc Fawr and its reclassification from Pedwar to 400m Sub-Pedwar is due to the analysis of LIDAR data by Aled Williams.  LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales.

Aled’s analysis of LIDAR data gives the hill the following details:


Fainc Fawr

Summit Height:  466.2m 

Summit Grid Reference:  SN 74150 89367

Bwlch Height:  437.9m

Bwlch Grid Reference:  SN 74446 89672

Drop:  28.3m


Therefore, the 466.2m LIDAR data produced for the summit position at SN 74150 89367 and the 437.9m LIDAR data produced for the bwlch position at SN 74446 89672 gives this hill 28.3m of drop which is insufficient for its continued inclusion as a Pedwar.


The full details for the hill are:

Cardinal Hill:  Banc Llechwedd Mawr

Summit Height:  466.2m (LIDAR data)

Name:  Fainc Fawr

OS 1:50,000 map:  135

Summit Grid Reference:  SN 74150 89367

Drop:  28.3m (LIDAR data)


This reclassification now brings the total for Y Pedwarau to 443 hills with eight additions, and twelve reclassifications to 400m Sub-Pedwar status since publication of the list by Europeaklist in May 2013.

The overall total for the 400m Sub-Pedwarau is now 219 with 21 hills being added and 15 hills being taken out of this category since publication of the list by Europeaklist in May 2013.

The list of Pedwar hills is available from the Haroldstreet website (January 2014) with all subsequent changes detailed on the Mapping Mountains site, with the list also having commenced publication on Mapping Mountains on the 30.01.17.

For the additions, reclassifications and deletions to Y Pedwarau reported on Mapping Mountains since the May 2013 publication of the list by Europeaklist please consult the following Change Registers:











Myrddyn Phillips and Aled Williams (May 2017)


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