Bryn Bedd (SN 671 475) – Sub-Trichant reclassified to Trichant
There has been a reclassification 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 LIDAR analysis conducted by Myrddyn Phillips.
LIDAR image of Bryn Bedd (SN 671 475) |
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.
Y Trichant - The 300m Hills of Wales by Myrddyn Phillips |
When the original 300m height band of Welsh P30 hills was published on Geoff Crowder’s v-g.me website, this hill was included in the Hills to be surveyed sub list, as it was considered not to meet the criteria then used for the main P30 category.
When 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 an estimated c 28m of drop, based on the 354m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 326m bwlch height based on interpolation of 10m contouring between 320m – 330m.
Extract from the Ordnance Survey 1:25,000 Explorer map |
However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed. The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales.
Therefore, the reclassification of this hill from Sub-Trichant status is due to LIDAR analysis, resulting in a 353.9m summit height and a 322.3m bwlch height, with these values giving this hill 31.5m of drop, which is sufficient for it to be classified as a Trichant.
The full details for the hill are:
Group: Elenydd
Name: Bryn Bedd
OS 1:50,000 map: 146
Summit Height: 353.9m (LIDAR)
Summit Grid Reference: SN 67137 47549 (LIDAR)
Bwlch Height: 322.3m (LIDAR)
Bwlch Grid Reference: SN 67294 47369 (LIDAR)
Drop: 31.5m (LIDAR)
Myrddyn Phillips
(November 2021)
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