Nant y Frân (SH 389 923) – Welsh P15 reclassified to Welsh Sub-P15
There has been a reclassification to the list of The Welsh P15s, 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 Nant y Frân (SH 389 923) |
The Welsh P15s – Welsh hills with 15m minimum drop, irrespective of their height, with an accompanying sub list entitled the Welsh Sub-P15s, with the criteria for this sub category being all Welsh hills with 14m or more and below 15m of drop. The list is authored by Myrddyn Phillips, with the Introduction to the list appearing on Mapping Mountains on the 10th May 2019.
The Welsh P15s by Myrddyn Phillips |
When the listing that became known as The Welsh P15s was being compiled, this hill was included in the main P15 list with 15m of drop, based on the 49m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and the 34m bwlch spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map.
Extract from the Ordnance Survey 1:25,000 Explorer map |
Therefore, the reclassification of this hill to Welsh Sub-P15 status is due to LIDAR analysis, resulting in a 49.4m summit height and a 34.7m bwlch height, with these values giving this hill 14.7m of drop, which is insufficient for it to be included in the main list of The Welsh P15s.
The full details for the hill are:
Group: Ynys Môn
Name: Nant y Frân
OS 1:50,000 map: 114
Summit Height: 49.4m (LIDAR)
Summit Grid Reference: SH 38928 92356 (LIDAR)
Bwlch Height: 34.7m (LIDAR)
Bwlch Grid Reference: SH 38859 92572 (LIDAR)
Drop: 14.7m (LIDAR)
Myrddyn Phillips (July
2021)
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