Darren (SH 825 087) – Sub-Trichant addition
There has been an addition to the list of Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill derived from detail on contemporary maps produced from Ordnance Survey data.
The criteria for the list that this addition applies to are:
Y Trichant
– The 300m Hills of Wales – Welsh
hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the
Sub-Trichant, with the criteria for this sub category being all Welsh hills at
or above 300m and below 400m in height with 20m or more and below 30m of
drop. The list is authored by Myrddyn Phillips with the
Introduction to the list and the renaming of it appearing on Mapping Mountains
on the 13th May 2017, and the Introduction to the Mapping Mountains
publication of the list appearing on the 1st January 2022.
Y Trichant - The 300m Hills of Wales by Myrddyn Phillips |
When the original 300m 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 with 29m of drop, based on the 324m summit spot height that appears on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer map and the 295m bwlch spot height that appears on the Ordnance Survey 1:25,000 Explorer map.
Extract from the Ordnance Survey 1:25,000 Explorer map |
One of the resources recently available online is the mapping on the OS Maps website and the details for this hill were subsequently re-assessed against this mapping. This is the replacement for OS Get-a-map and until recent times had contours at 5m intervals which were proving consistently more accurate compared to the 5m contours that sometimes appear on the Ordnance Survey 1:25,000 Explorer map and used to appear on the online Vector Map Local. This mapping had bwlch contouring between 295m – 300m, with interpolation placing the height of the bwlch as an estimated c 296m, with these contours also represented on other 5m contouring available online.
Extract from online 5m contouring |
The full details for the hill are:
Group: Aran Fawddwy
Name: Darren
OS 1:50,000 map: 124,
125
Summit Height: 324m (spot height)
Summit Grid Reference: SH 82563 08709 (spot height)
Bwlch Height: c 296m (interpolation)
Bwlch Grid Reference: SH 82391 09148 (interpolation)
Drop: c 28m (spot height summit and interpolated bwlch)
Myrddyn Phillips
(February 2022)
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