The Y
Pedwarau list has been updated with the Moel Hebog group of hills
Tuesday, 28 February 2017
Sunday, 26 February 2017
Mapping Mountains – Hill Reclassifications – Y Trechol – The Dominant Hills of Wales
Ynys Hir (SH 566 396) - Dominant addition
There has been an addition to the listing of Y Trechol – The Dominant Hills of Wales due to a survey with the Trimble GeoXH 6000. This has resulted in the hill being added to the Dominant list. With the criteria for inclusion to this list being those Welsh P30 hills whose prominence equal or exceed half that of their absolute height.
The details relating to this
hill’s inclusion as a Dominant hill are
retrospective as it was surveyed on the 1st February 2014 and later
appeared in the Moel Hebog group of Dominant hills when published on the Mappingn Mountains site on the 28th January 2016.
Prior to the survey with the
Trimble this hill was unclassified as the Ordnance Survey 1:50,000 Landranger
map, 1:25,000 Explorer map and the enlarged mapping hosted on the Geograph
website all give the hill an uppermost 20m ring contour, implying that its
height is not sufficient for P30 status and consideration as a Dominant hill. However, it was Aled Williams who first
proposed that this hill may attain P30 status and it was subsequently surveyed
in his company.
The hill is in the Moel Hebog group of hills and is placed
in the Region of North Wales (Region A, Sub-Region A1) and is situated between
the communities of Porthmadog to its
south and Tremadog to its north
north-west, with the A 487 road to its immediate south. The hill can be visited from this road where
a lay-by gives access through a gate into the woodland that covers this and the
other adjacent small hills.
The name of the hill is Ynys Hir and as its name implies it
forms an island, which is now landlocked, it is included as a Dominant hill as the survey with the
Trimble GeoXH 6000 produced a summit height of 37.3m, and with an estimated
bwlch height of c 3m it gives this hill 91.21% Dominance.
The full details for the hill are:
Group: Moel Hebog
Name: Ynys Hir
Dominance: 91.21%
OS 1:50,000 map: 124
Summit Grid Reference: SH
56695 39693
Summit Height: 37.3m (converted to OSGM15)
Drop Summit to Bwlch: c 34m
Drop Bwlch to ODN: c
3m
 |
| Beyond the cliffs and immersed in woodland is the summit of Ynys Hir (SH 566 396) which is now classified as a Dominant hill |
Myrddyn Phillips (February 2017)
Friday, 24 February 2017
Mapping Mountains – Hill Reclassifications – Y Trechol – The Dominant Hills of Wales
Dinas Dinlle (SH 436
564) - Dominant addition
There has been an addition to the listing of Y Trechol – The Dominant Hills of Wales due to detail included on the Ordnance Survey enlarged mapping hosted on the Geograph website and which was first spotted by Chris Watson, and subsequently confirmed via a survey with the Trimble GeoXH 6000. This has resulted in the hill being added to the Dominant list. With the criteria for inclusion to this list being those Welsh P30 hills whose prominence equal or exceed half that of their absolute height.
The details relating to this
hill’s inclusion as a Dominant hill
are retrospective as it was added to the list shortly after its initial
compilation and later appeared in the Moel
Hebog group of hills when published on Mapping Mountains on the 28th
January 2016.
Prior to Chris Watson raising the probability
of this hill being a P30 and its subsequent inclusion as a Dominant hill it had remained unclassified, as the Ordnance Survey
1:50,000 Landranger map gave a 31m summit spot height and bwlch contouring
between 0m – 10m, whilst the 1:25,000 Explorer map gave an uppermost 30m ring
contour and the same bwlch contouring, which implied that the hill did not have
the required 30m of drop to be considered for Dominant status.
The hill is positioned in the Moel Hebog group of hills and is placed
in the Region of North Wales (Region A, Sub-Region A1) and is situated on the
outskirts of the small community that takes its name from the hill; Dinas Dinlle, and is positioned with the
sea to its immediate west which has eroded much of its slopes over recent
years. If wanting to visit the hill it
can be easily accessed from the car park adjacent to the sea front from where a
path heads up its northern slopes.
The name of the hill is Dinas Dinlle and as its name implies the upper section of the hill comprises an ancient hill fort, it was included as a 30-99m Twmpau as the Ordnance Survey enlarged mapping hosted on the Geograph website has contours at 5m intervals giving the hill an uppermost contour of 35m and bwlch contouring between 0m – 5m, these values give the hill an estimated drop of c 31m – c 32m. The summit of this hill has subsequently been surveyed with the Trimble GeoXH 6000 as 34.7m (converted to OSGM15) and with a 4.1m bwlch height ascertained from LIDAR analyis, these values give this hill 30.6m of drop and 88.22% dominance.
The full details for the hill are:
Group: Moel Hebog
Name: Dinas Dinlle
Dominance: 88.22%
OS 1:50,000 map: 115, 123
Summit Grid Reference: SH 43676
56438
Summit Height: 34.7m (converted to OSGM15)
Drop Summit to Bwlch: 30.6m
Drop Bwlch to ODN: 4.1m
 |
| Dinas Dinlle (SH 436 564) now classified as a Dominant hill |
Myrddyn Phillips (February 2017)
Wednesday, 22 February 2017
Change Register - The 500-Metre Tops of Ireland - 490m Double Subs
Change
Register
The
500-Metre Tops of Ireland
490m
Double Subs
The
500-Metre Tops of Ireland are the Irish hills at or above 500m and
below 609.6m (2,000ft) in height that have a minimum drop of 30m. The list is co-authored by Michael Dewey and
Myrddyn Phillips with each having produced a version of the list independent of
the other. Michael’s list originated in
1998 and comprised 186 hills, whilst Myrddyn’s list originated in 2000 and
comprised 191 hills with a further 29 hills listed in a sub list entitled
‘Hills that need on the spot surveying with the prospect of being future
additions’, this sub list forms the basis of the 500m Subs that now accompanies the main P30 list.
The list produced by Myrddyn was sent to a number of people
including Michael Dewey and the Mountaineering Council of Ireland (now named
Mountaineering Ireland). Having produced
versions of the same list the two authors combined each and decided to produce
one co-authored list. Data were
re-evaluated and the updated co-authored list was sent to the Mountaineering
Council of Ireland and later formed the lower height band of the list that
appeared on the fledging MountainViews website in 2002, this list was later
named the Arderins in 2009, with the higher height band of this list using data
from the late Joss Lynam’s 600m Irish list.
The
500-Metre Tops of Ireland listing was next fully re-evaluated with
assistance from Jim Bloomer prior to it being published on the Hill Bagging
website on 1st June 2011, and it was then published in the
downloadable Access and Excel versions (v12.0) of the Database of British and
Irish Hills (DoBIH) on 27th November 2011. During this process the original sub list was
also fully re-evaluated and appeared in the Hill Bagging publication entitled subMyrddynDewey, this sub list is
referred to as the 500m Subs in the
Change Registers published on Mapping Mountains.
However, it wasn’t until the Hill Bagging publication and
the subsequent Database of British and Irish Hills (DoBIH) publication that the
listing included two other sub categories; the 490m Subs and the 490m Double
Subs and this Change Register details those hills that are, or have been
listed within the 490m Double Subs category. These two sub categories are not officially
tied to The 500-Metre Tops of Ireland list
on either the Hill Bagging or the DoBIH publication, but these data were
sourced from The 400-Metre Tops of
Ireland list compiled by Myrddyn Phillips and subsequently duplicated by
MountainViews and renamed The Carns. As these data are officially a part of The 500-Metre Tops of Ireland list, the
hills incorporated are documented in this Change Register. The 490m
Double Subs comprise all Irish hills that fail to meet the The 500-Metre Tops of Ireland qualification
by less than 10m of height and also less than 10m of drop, these are the hills
that are 490m or more and below 500m in height that have 20m or more and below
30m of drop, they are known as the 490m
Double Subs.
Although the criteria has remained the same The 500-Metre Tops of Ireland list has
changed greatly since its first publication with the advent of independent
surveyors enabling greater accuracy for numerical data, and the meticulous
research conducted by Paul Tempan and incorporated by MountainViews, the listing
also now incorporates three Sub categories, the 500m Subs, the 490m Subs and
the 490m Double Subs which this
Change Register details.
It seems fitting that the list of The 500-Metre Tops of Ireland – 490m Double Subs should now benefit
from a detailed Change Register, and although the compilation to this sub list
took place when the data were re-evaluated prior to publication on the Hill
Bagging website in 2011, it is prudent for this Change Register to initially
detail the changes to the list since this publication.
The Change Register to The
500-Metre Tops of Ireland – 490m Double Subs appears below with the
reclassifications to the list being detailed chronologically in receding order.
Change
Register
The
500-Metre Tops of Ireland
490m
Double Subs
As of
yet there are no reclassifications to this sub list since June 2011 publication
by Hill Bagging.
27th
November 2011 – Database of British and Irish Hills publishes The 500-Metre Tops of Ireland.
The
500-Metre Tops of Ireland – 490m Double Subs total confirmed as 4.
1st
June 2011 – Hill Bagging publishes The
500-Metre Tops of Ireland.
The
500-Metre Tops of Ireland – 490m Double Subs total confirmed as 4.
Michael Dewey and Myrddyn Phillips (February 2017)
Tuesday, 21 February 2017
Mapping Mountains – Hill Reclassifications – Y Trechol – The Dominant Hills of Wales
Geirth Mawr (SH 535
393) - Dominant deletion
There has been confirmation of a deletion from the list of the Y Trechol – The Dominant Hills of Wales, with the summit height, bwlch height and their locations, the drop, dominance and status of the hill derived from detail on contemporary maps produced from Ordnance Survey data and confirmed from subsequent LIDAR analysis conducted by Myrddyn Phillips.
%20-%20LIDAR%20hill%201.jpg)
LIDAR image of Geirth Mawr (SH 535 393)
The criteria for the list that this deletion applies to are:
Y Trechol - The Dominant Hills of Wales - Welsh P30 hills whose prominence equal or exceed half that of their absolute height. With the criteria for Lesser Dominant status being those additional Welsh P30 hills whose prominence is between one third and half that of their absolute height. The list is authored by Myrddyn Phillips with the Introduction to the start of the Mapping Mountains publication of this list appearing on the 3rd December 2015, and the list is now available in its entirety on Mapping Mountains in Google Doc format.
Y Trechol - The Dominant Hills of Wales by Myrddyn Phillips
The name the hill is listed by is Geirth Mawr, and it is adjoined to the Moel Hebog 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 A497 road to its north and minor roads to its west and east, and has the town of Porthmadog towards the east.
When the original 30-99m height band of Welsh P30 hills were 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 30m of drop, based on an estimated c 58m summit height, based on interpolation of 10m contouring and the 28m bwlch spot height that appears on the Ordnance Survey 1:25,000 Explorer map, resulting in a dominance value of 51.72%, which was sufficient for Dominant status.
%20-%201%2025000.jpg)
Extract from the Ordnance Survey 1:25,000 Explorer map
Since the original publication of the Welsh P30
lists on Geoff Crowder’s v-g.me website there have been a number of 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.
The details for this hill were re-assessed when the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map became available online. This mapping had many spot heights not on other publicly available Ordnance Survey maps and for this hill it had a 56m summit spot height, resulting in its drop value being amended to 28m, which is insufficient for continued Dominant status.
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 confirmation of the deletion of this hill from Dominant status is due to LIDAR
analysis, resulting in a 57.4m summit height and a 27.9m bwlch height, with
these values giving this hill 29.5m of drop, which is insufficient for Dominant status.
The full details for the hill are:
Group: Moel Hebog
Name: Geirth Mawr
OS 1:50,000 map: 124
Summit Height: 57.4m
(LIDAR)
Summit Grid Reference:
SH 53511 39363 (LIDAR)
Bwlch Height: 27.9m
(LIDAR)
Bwlch Grid Reference:
SH 53302 39651 & SH 53311 39649 (LIDAR)
Drop: 29.5m (LIDAR)
Dominance: N/A (insufficient drop)
Myrddyn Phillips (February 2017)
Monday, 20 February 2017
Mapping Mountains - Y Pedwarau - The 400m Hills of Wales - Yr Wyddfa group of hills published
The Y
Pedwarau list has been updated with the Yr Wyddfa group of hills
Sunday, 19 February 2017
Change Register - The 500-Metre Tops of Ireland - 490m Subs
Change
Register
The
500-Metre Tops of Ireland
490m
Subs
The
500-Metre Tops of Ireland are the Irish hills at or above 500m and
below 609.6m (2,000ft) in height that have a minimum drop of 30m. The list is co-authored by Michael Dewey and
Myrddyn Phillips with each having produced a version of the list independent of
the other. Michael’s list originated in
1998 and comprised 186 hills, whilst Myrddyn’s list originated in 2000 and
comprised 191 hills with a further 29 hills listed in a sub list entitled
‘Hills that need on the spot surveying with the prospect of being future
additions’, this sub list forms the basis of the 500m Subs that now accompanies the main P30 list.
The list produced by Myrddyn was sent to a number of people
including Michael Dewey and the Mountaineering Council of Ireland (now named
Mountaineering Ireland). Having produced
versions of the same list the two authors combined each and decided to produce
one co-authored list. Data were
re-evaluated and the updated co-authored list was sent to the Mountaineering
Council of Ireland and later formed the lower height band of the list that
appeared on the fledging MountainViews website in 2002, this list was later
named the Arderins in 2009, with the higher height band of this list using data
from the late Joss Lynam’s 600m Irish list.
The
500-Metre Tops of Ireland listing was next fully re-evaluated with
assistance from Jim Bloomer prior to it being published on the Hill Bagging
website on 1st June 2011, and it was then published in the
downloadable Access and Excel versions (v12.0) of the Database of British and
Irish Hills (DoBIH) on 27th November 2011. During this process the original sub list was
also fully re-evaluated and appeared in the Hill Bagging publication entitled subMyrddynDewey, this sub list is
referred to as the 500m Subs in the
Change Registers published on Mapping Mountains.
However, it wasn’t until the Hill Bagging publication and
the subsequent Database of British and Irish Hills (DoBIH) publication that the
listing included two other sub categories; the 490m Subs and the 490m Double
Subs and this Change Register details those hills that are, or have been
listed within the 490m Subs category. These two sub categories are not officially
tied to The 500-Metre Tops of Ireland list
on either the Hill Bagging or the DoBIH publication, but these data were
sourced from The 400-Metre Tops of
Ireland list compiled by Myrddyn Phillips and subsequently duplicated by
MountainViews and renamed The Carns. As these data are officially a part of The 500-Metre Tops of Ireland list, the
hills incorporated are documented in this Change Register. The 490m
Subs comprise all Irish hills that fail to meet The 500-Metre Tops of Ireland qualification by 10m or less of
height, these are the hills that are 490m or more and below 500m in height that
have a minimum 30m of drop.
Although the criteria has remained the same The 500-Metre Tops of Ireland list has
changed greatly since its first publication with the advent of independent
surveyors enabling greater accuracy for numerical data, and the meticulous
research conducted by Paul Tempan and incorporated by MountainViews, the
listing also now incorporates three Sub categories, the 500m Subs, the 490m Subs which
this Change Register details and the 490m
Double Subs.
It seems fitting that the list of The 500-Metre Tops of Ireland – 490m Subs should now benefit from a
detailed Change Register, and although the compilation to this sub list took place
when the data were re-evaluated prior to publication on the Hill Bagging
website in 2011, it is prudent for this Change Register to initially detail the
changes to the list since this publication.
The Change Register to The
500-Metre Tops of Ireland – 490m Subs appears below with the
reclassifications to the list being detailed chronologically in receding order.
Change
Register
The
500-Metre Tops of Ireland
490m
Subs
As of
yet there are no reclassifications to this sub list since June 2011 publication
by Hill Bagging.
27th
November 2011 – Database of British and Irish Hills publishes The 500-Metre Tops of Ireland.
The
500-Metre Tops of Ireland – 490m Subs total confirmed as 22.
1st
June 2011 – Hill Bagging publishes The
500-Metre Tops of Ireland.
The
500-Metre Tops of Ireland – 490m Subs total confirmed as 22.
Michael Dewey and Myrddyn Phillips (February 2017)
Saturday, 18 February 2017
Mapping Mountains – Hill Reclassifications – Y Trechol – The Dominant Hills of Wales
Coed Bodlondeb (SH 779
781) - Dominant addition
There has been an addition to the listing of Y Trechol – The Dominant Hills of Wales due to detail included on the Ordnance Survey enlarged mapping hosted on the Geograph website. This has resulted in the hill being added to the Dominant list. With the criteria for inclusion to this list being those Welsh P30 hills whose prominence equal or exceed half that of their absolute height.
The details relating to this hill’s
inclusion as a Dominant hill are retrospective
as it appeared in the Carneddau group
of hills when published on Mapping Mountains on the 17th December 2015.
Prior to this hill’s inclusion as a Dominant hill it was listed with an estimated c 27m of drop based on the Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps giving the hill an uppermost 50m ring contour and bwlch contouring between 20m – 30m, resulting in an estimated summit height of c 53m and an estimated bwlch height of c 26m.
The hill is in the Carneddau group of hills and is placed in the Region of North Wales (Region A, Sub-Region A1) and is situated on the outskirts of Conwy with the Afon Conwy to its immediate north and east.
The hill is in the Carneddau group of hills and is placed in the Region of North Wales (Region A, Sub-Region A1) and is situated on the outskirts of Conwy with the Afon Conwy to its immediate north and east.
If wanting to visit the hill it
can be accessed relatively easily with public parking available next to where the
Offices are marked to the south of the summit on Ordnance Survey maps. There are a number of paths marked on the map
that head up to, or contour around the summit, and as the name of the hill
suggests it is part of a wood which consists of deciduous trees.
The name of the hill is Coed Bodlondeb and it is included as a Dominant hill as the Ordnance Survey
enlarged map hosted on the Geograph website has contours at 5m intervals giving
the hill an uppermost contour of 55m and bwlch contouring between 20m – 25m. Therefore the summit is estimated as being c
57m high and the bwlch estimated as being c 23m high, with these values giving
this hill c 34m of drop and 59.65% Dominance.
Since this hill was originally included in the Y Trechol - The Dominant Hills of Wales list the summit has been surveyed with the Trimble GeoXH 6000 and the bwlch of the hill has been analysed via LIDAR and the resulting values are given below.
Since this hill was originally included in the Y Trechol - The Dominant Hills of Wales list the summit has been surveyed with the Trimble GeoXH 6000 and the bwlch of the hill has been analysed via LIDAR and the resulting values are given below.
The full details for the hill are:
Cardinal Hill: Tal y Fan
Name: Coed Bodlondeb
OS 1:50,000 map: 115
Summit Height: 55.6m (converted to OSGM15)
Summit Grid Reference: SH 77921 78114
Summit Grid Reference: SH 77921 78114
Drop Summit to Bwlch: 32.6m (Trimble summit and LIDAR bwlch)
Bwlch Grid Reference: SH 77852 77725 (LIDAR)
Dominance: 58.70%
Drop Bwlch to ODN: 22.9m (LIDAR)
Bwlch Grid Reference: SH 77852 77725 (LIDAR)
 |
| Gathering data at the summit of Coed Bodlondeb |
For details on the summit survey of Coed Bodlondeb
Myrddyn Phillips (February 2017)
Thursday, 16 February 2017
Change Register - The 500-Metre Tops of Ireland - 500m Subs
Change
Register
The
500-Metre Tops of Ireland
500m
Subs
The
500-Metre Tops of Ireland are the Irish hills at or above 500m and
below 609.6m (2,000ft) in height that have a minimum drop of 30m. The list is co-authored by Michael Dewey and
Myrddyn Phillips with each having produced a version of the list independent of
the other. Michael’s list originated in 1998
and comprised 186 hills, whilst Myrddyn’s list originated in 2000 and comprised
191 hills with a further 29 hills listed in a sub list entitled ‘Hills that
need on the spot surveying with the prospect of being future additions’, this
sub list forms the basis of the 500m Subs
that now accompanies the main P30 list.
The list produced by Myrddyn was sent to a number of people including Michael Dewey and the Mountaineering Council of Ireland (now named Mountaineering Ireland). Having produced versions of the same list the two authors combined each and decided to produce one co-authored list. Data were re-evaluated and the updated co-authored list was sent to the Mountaineering Council of Ireland and later formed the lower height band of the list that appeared on the fledging MountainViews website in 2002, this list was later named the Arderins in 2009, with the higher height band of this list using data from the late Joss Lynam’s 600m Irish list.
The compilation originally sent to the Mountaineering Council of Ireland included a sub list entitled ‘Hills that need on the spot surveying with the prospect of being future additions.’ This sub list comprised all hills identified from map study that were at or above 500m and below 609.6m (2,000ft) in height and if surveyed for drop stood a chance of qualifying for the main P30 list. At the time of compilation the spot heights on Ordnance Survey of Ireland and Ordnance Survey of Northern Ireland maps were taken at face value as the margin of uncertainty applicable to the surveying method that ascertained them was unknown at the time. Therefore if a hill was given a drop value of 29m from its summit and col spot heights it was not included in this ‘Hills to be surveyed’ sub list as it was deemed not to warrant a survey for inclusion into the main P30 list as the map had given it 29m of drop. This sub list has now been standardised and comprises all Irish hills that are at or above 500m and below 609.6m (2,000ft) in height and have 20m or more and below 30m of drop, the name of this sub list is the 500m Subs.
The compilation originally sent to the Mountaineering Council of Ireland included a sub list entitled ‘Hills that need on the spot surveying with the prospect of being future additions.’ This sub list comprised all hills identified from map study that were at or above 500m and below 609.6m (2,000ft) in height and if surveyed for drop stood a chance of qualifying for the main P30 list. At the time of compilation the spot heights on Ordnance Survey of Ireland and Ordnance Survey of Northern Ireland maps were taken at face value as the margin of uncertainty applicable to the surveying method that ascertained them was unknown at the time. Therefore if a hill was given a drop value of 29m from its summit and col spot heights it was not included in this ‘Hills to be surveyed’ sub list as it was deemed not to warrant a survey for inclusion into the main P30 list as the map had given it 29m of drop. This sub list has now been standardised and comprises all Irish hills that are at or above 500m and below 609.6m (2,000ft) in height and have 20m or more and below 30m of drop, the name of this sub list is the 500m Subs.
The
500-Metre Tops of Ireland listing was next fully re-evaluated with assistance
from Jim Bloomer prior to it being published on the Hill Bagging website on 1st
June 2011, and it was then published in the downloadable Access and Excel versions
(v12.0) of the Database of British and Irish Hills (DoBIH) on 27th
November 2011. During this process the original
sub list was fully re-evaluated and appeared in the Hill Bagging publication
entitled subMyrddynDewey, this sub
list is referred to as the 500m Subs
in this Change Register.
Although the criteria has remained the same the list has
changed greatly since its first publication with the advent of independent
surveyors enabling greater accuracy for numerical data, and the meticulous
research conducted by Paul Tempan and incorporated by MountainViews, the
listing also now incorporates three Sub categories, the 500m Subs which this Change Register details, the 490m Subs and the 490m Double Subs.
It seems fitting that the list of The 500-Metre Tops of Ireland – 500m Subs should now benefit from a
detailed Change Register, and although the majority of updates to this sub list
took place when the data were re-evaluated prior to publication on the Hill
Bagging website in 2011, it is prudent for this Change Register to initially
detail the changes to the list since this publication.
The Change Register to The
500-Metre Tops of Ireland – 500m Subs appears below with the
reclassifications to the list being detailed chronologically in receding order.
Change
Register
The
500-Metre Tops of Ireland
500m
Subs
Pigeon Rock
Mountain North Top 534m at J 261 250
This hill’s inclusion in the 500m Subs list was announced on the Mapping Mountains site on 24.08.16,
the hill was not previously listed in the 500m
Subs as assessment of contour interpolation had given it only c 19m of
drop, just under the 20m minimum drop required to qualify for this sub list. However, upon Jim Bloomer’s suggestion to re-assess
this hill’s data it was included in the 500m
Subs and listed with a 534m summit height based on the spot height on the Ordnance
Survey of Northern Ireland 1:50,000 Discoverer Series map 29, the Harvey map and
the Mournes Activity map, and an interpolated col height of c 514m, which gave
this hill a listed drop of c 20m, this is sufficient for this hill’s inclusion
in this sub category. The 500-Metre Tops of Ireland – 500m Subs total
increases by one and confirmed as 58.
Knocknaveacal
North Top 509.1m at V 74438 56269
This is the first hill to be reclassified to the 500m Subs
list from the main P30 list, and its reclassification was announced on the
Mapping Mountains site on 06.11.15, the hill was previously listed as a 500m
P30 based on the 513m summit spot height that appears on the Ordnance Survey of
Ireland 1:50,000 Discovery Series map 84 and an interpolated col height of c
482m, which gave this hill a listed drop of c 31m. The hill was subsequently surveyed by John
Fitzgerald on the 30.05.15 with a Trimble GeoXH 6000 resulting in a 509.1m
summit height and 482.6m col height, the surveyed drop of 26.5m is insufficient
for this hill’s retention in The
500-Metre Tops of Ireland list and it is now reclassified to a 500m Sub. The
500-Metre Tops of Ireland – 500m Subs total increases by one and confirmed
as 57.
27th
November 2011 – Database of British and Irish Hills publishes The 500-Metre Tops of Ireland.
The
500-Metre Tops of Ireland – 500m Subs total confirmed as 56.
1st
June 2011 – Hill Bagging publishes The
500-Metre Tops of Ireland.
The
500-Metre Tops of Ireland – 500m Subs total confirmed as 56.
Michael Dewey and Myrddyn Phillips (February 2017)