Sunday 23 June 2019

Mapping Mountains – Hill Reclassifications – Hewitts


Bera Mawr (SH 674 682) – Hewitt reclassified to SubHewitt

This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Welsh Hewitts (an acronym for Hill in England, Wales or Ireland over Two Thousand feet high).  These reclassification posts will give details of hills where I have direct association with their change of status, and they will tie in with a forthcoming Change Register giving detail to this list and its alterations since first publication.

The listing of Welsh Hewitts was published in booklet format by TACit Tables in February 1997 and entitled The Hewitts and Marilyns of Wales.  This list evolved out of The Absolute Summits of England and Wales which were known as the Sweats (an acronym for Summits in Wales and England Above Two-thousand FEET) and which was published by Cicerone Press in 1992 in the book entitled The Relative Hills of Britain.  The list compiler for the Hewitts and the preceding Sweats is Alan Dawson.

When the Welsh Hewitts list was published in booklet format there were 137 qualifying hills listed with their criteria being any Welsh hill at or above 2000ft (609.6m) in height with 30m minimum drop, accompanying the main list are two sub category’s entitled SubHewitts, with the two sets of criteria being any Welsh hill at or above 600m and below 2000ft (609.6m) in height that have a minimum drop of 30m and any Welsh hill at or above 2000ft (609.6m) in height with 20m or more and below 30m of drop.

The Hewitts and Marilyns of Wales by Alan Dawson

The details for the hill reclassification appear below:

The name of the hill is Bera Mawr, and it is adjoined to the Carneddau group of hills, and it is positioned with the A55 road and the north Wales coast to its north-west, and has the city of Bangor towards its west north-west.

Bera Mawr (SH 674 682)

Prior to this hill’s reclassification to SubHewitt status it was listed as a Hewitt with an estimated c 30m of drop based on the 794m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and an estimated bwlch height of c 764m.

As the estimated drop value of c 30m is the minimum required for Hewitt status it was prioritised for a GNSS survey and this took place on the 10st March 2014.  The hill was surveyed by Myrddyn Phillips using a Trimble GeoXH 6000 to determine the summit and bwlch height and also its drop value.  The survey resulted in a 793.6m summit height and a 763.9m bwlch height, with these values giving this hill 29.7m of drop, with these details being forwarded to the list author.

The Trimble GeoXH 6000 gathering data at the summit of Bera Mawr

The details for this hill were then analysed via LIDAR by Aled Williams, resulting in a 792.98m summit height and a 764.04m bwlch height, with these values giving this hill 28.94m of drop.

LIDAR image of Bera Mawr

The hill was subsequently surveyed by Alan Dawson using a Leica RX1250 on the 14th June 2017, resulting in a 793.7m summit height and a prioritised bwlch height and position taken from the data previously produced by the Trimble GeoXH 6000 survey and LIDAR analysis. 

The reclassification of this hill from Hewitt to SubHewitt status was accepted by the list author and its new classification augmented in to the listing of the Hewitts in July 2017.


The full details for the hill are:

Name:  Bera Mawr

OS 1:50,000 map:  115

OS 1:25,000 map:  17

Summit Height:  793.7m (converted to OSGM15)

Summit Grid Reference:  SH 67485 68274 (as listed in the Hewitts)

Bwlch Height:  764.0m (as listed in the Hewitts)

Bwlch Grid Reference:  SH 6751 6815 (as listed in the Hewitts)

Drop:  29.7m (as listed in the Hewitts)


Myrddyn Phillips (June 2019)




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