Mapping Mountains – Significant Name Changes – The Welsh P15s

 

Melin Llanddyfnan (SH 483 786) 

There has been a Significant Name Change 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 Ynys Llanddyfnan (SH 483 786)

The criteria for the list that this name change applies to are:

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 10^th May 2019. 

The Welsh P15s by Myrddyn Phillips

The hill is adjoined to the Ynys Môn group of hills, which are situated in the north-western part of North Wales (Region A, Sub-Region A1), and it is positioned with the coast to its north-east, a minor road to its immediate north-west and south, the B5110 road farther to its north-west and the B5109 road to its south-east, and has the town of Llangefni towards the south-west. 

When the listing that became known as The Welsh P15s was being compiled, this hill was listed under the point (Pt. c 86m) notation with an estimated c 13m of drop, based on an estimated c 86m summit height and an estimated c 73m bwlch height, with both heights based on interpolation of 5m contouring that appear on the Ordnance Survey 1:25,000 Explorer map. 

Extract from the Ordnance Survey 1:25,000 Explorer map

The name of Melin Llanddyfnan is taken from online sources, of which there are a number, mainly based on the history of, and the relatively recent reconstruction of the windmill.  The boundary taking in land adjoined to Melin Llanddyfnan has also been substantiated by the Tithe map. 

Extract from the Ordnance Survey Six-Inch map hosted as a part of the Tithe map

Therefore, the name this hill is now listed by in The Welsh P15s is Melin Llanddyfnan and this was derived from online sources, with the boundary incorporating Melin Llanddyfnan substantiated via the Tithe map. 

 

The full details for the hill are: 

Group:  Ynys Môn 

Name:  Melin Llanddyfnan

Previously Listed Name:  Pt. c 86m 

OS 1:50,000 map:  114, 115

Summit Height:  87.2m (LIDAR)                                                           

Summit Grid Reference:  SH 48371 78617 (LIDAR) 

Bwlch Height:  72.2m (LIDAR) 

Bwlch Grid Reference:  SH 48391 79121 (LIDAR) 

Drop:  14.9m (LIDAR) 

 

Myrddyn Phillips (October 2021)