Craig Dinas (SH 280 772)
There has been a Significant Height Revision to a hill that is listed in 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 Craig Dinas (SH 280 772) |
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 listed with an estimated c 16m of drop, based on the 19m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 3m bwlch height based on interpolation of 5m contouring between 0 – 5m.
Extract from the Ordnance Survey 1:25,000 Explorer map |
The summit height produced by LIDAR analysis is 20.0m and this comes within the parameters of the Significant Height Revisions used within this page heading, these parameters are:
The term Significant Height Revisions applies to any listed hill whose interpolated height and Ordnance Survey or Harvey map summit spot height has a 2m or more discrepancy when compared to the survey result produced by the Trimble GeoXH 6000 or analysis of data produced via LIDAR, also included are hills whose summit map data is missing an uppermost ring contour when compared to the data produced by the Trimble or by LIDAR analysis.
LIDAR summit image of Craig Dinas |
The full details for the hill are:
Group: Ynys Môn
Name: Craig Dinas
OS 1:50,000 map: 114
Summit Height (New Height): 20.0m (LIDAR)
Summit Grid Reference: SH 28016 77284 (LIDAR)
Bwlch Height: 3.3m (LIDAR)
Bwlch Grid Reference: SH 27937 77186 (LIDAR)
Drop: 16.7m (LIDAR)
Myrddyn Phillips (May
2021)
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