Mapping Mountains – Significant Name Changes – The Welsh P15s

 

Craig Rofft (SH 776 831) 

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 Craig Rofft (SH 776 831)

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 Mynydd Hiraethog group of hills, which are situated in the northern part of North Wales (Region A, Sub-Region A2), and it is positioned encircled by minor roads, and has the town of Llandudno towards the south-east.

When the original 100m 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-assessed and it was listed under the transposed name of Mynydd Isaf with an estimated c 20m of drop, based on the 168m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and an estimated c 148m bwlch height, based on interpolation of 5m contouring 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

Since the initial compilation of this list there have been a number of Ordnance Survey maps made available online, some of these are historic such as the series of Six-Inch maps on the National Library of Scotland website.  Whilst others were digitally updated such as the Ordnance Survey Vector Map Local that was hosted on the Geograph website and which was entitled the Interactive Coverage Map.  Whilst others are current and digitally updated such as the interactive mapping on the Magic Maps and WalkLakes websites and it is the series of Ordnance Survey Six-Inch maps that form the basis of the change in the listed name of this hill. 

Extract from the Ordnance Survey series of Six-Inch maps

The Ordnance Survey series of Six-Inch maps formed the base map Ordnance Survey used for many decades leading to the production of the 1:10,000 Series of maps, both have now been superseded by the digitised Master Map.  The series of Six-Inch maps are excellent for name placement and especially so compared to the contemporary Ordnance Survey 1:25,000 Explorer map, and it is the series of Six-Inch maps that places the name of Craif Rofft adjacent to the summit of this hill.

Therefore, the name this hill is now listed by in The Welsh P15s is Craig Rofft and this was derived from the Ordnance Survey series of Six-Inch maps. 

 

The full details for the hill are: 

Group:  Mynydd Hiraethog 

Name:  Craig Rofft

Previously Listed Name:  Mynydd Isaf 

OS 1:50,000 map:  115

Summit Height:  167.6m (LIDAR) 

Summit Grid Reference:  SH 77614 83198 (LIDAR) 

Bwlch Height:  147.9m (LIDAR) 

Bwlch Grid Reference:  SH 77400 83151 (LIDAR) 

Drop:  19.7m (LIDAR) 

 

Myrddyn Phillips (October 2024)