Showing posts with label Bryn Mawr (SJ 251 190). Show all posts
Showing posts with label Bryn Mawr (SJ 251 190). Show all posts

Saturday, 11 November 2017

Mapping Mountains – Hill Reclassifications – Humps


Bryn Mawr (SJ 251 190) – Subhump addition

This is the twenty seventh in a series of Hill Reclassification posts that detail hills whose status has been altered in the listing of the Humps (HUndred Metre Prominences) through map study and / or surveys that I have conducted.

Bryn Mawr (SJ 251 190)

This and forthcoming posts are retrospective as many of these hill reclassifications were initiated from studying the Ordnance Survey enlarged mapping that is hosted on the Geograph website, or in this instance from a survey with the Trimble GeoXH 6000, and for the reclassifications that affected the Humps the survey of this hill took place on the 08.08.15.

The listing of Humps was published in book format by Lulu in 2009 and entitled More Relative Hills of Britain, its author; Mark Jackson gives credit to a number of people who contributed toward the formation of this list, these include; Eric Yeaman, Alan Dawson, Clem Clements, Rob Woodall, Bernie Hughes, Pete Ridges and others.  When the list was published in book format there were 2987 Humps listed with their criteria being any British hill that has 100m or more of drop, accompanying the main list is a sub category entitled Subhumps, with the criteria being any British hill that has 90m or more and below 100m of drop.

More Relative Hills of Britain by Mark Jackson

The details for the reclassification appear below:

There has been a reclassification to the listing of the Humps (HUndred Metre Prominences) instigated by a survey with the Trimble GeoXH 6000 which took place on the 08.08.15.

Prior to the survey with the Trimble GeoXH 6000 Mark Jackson had listed this hill with 85m of drop based on a 173m summit height and an 88m bwlch height. 

The hill is adjoined to the Carnedd Wen group of hills and is situated overlooking the B 4393 road which is to its north and east and the A 483 road to its south-east, and has the Montgomery Canal to its east and the Afon Efyrnwy (River Vyrnwy) to its north, and is positioned between the small communities of Llansantffraid-ym-Mechain to the west north-west, Llanymynech to the north-east, Four Crosses to the east south-east and Ardllin (Arddleen) towards the south.

Bryn Mawr was surveyed using a Trimble GeoXH 6000 by Myrddyn Phillips on the 08.08.15 resulting in a 90m drop value, with a summit height of 178.1m (converted to OSGM15) and a bwlch height of 88m based on the spot height that appears on the Ordnance Survey enlarged mapping hosted on the Geograph website, with this drop value being sufficient for this hill to be classified as a Subhump.

The addition of this hill to Subhump status was accepted by Mark Jackson on the 21.12.15 and the listing of the Humps was updated accordingly.

The Trimble GeoXH 6000 gathering data at the summit of Bryn Mawr

The full details for the hill are:

Name:  Bryn Mawr

Summit Height:  178m (178.1m converted to OSGM15)

OS 1:50,000 map:  126

OS 1:25,000 map:  240

Summit Grid Reference:  SJ 25119 19058 (as listed in the Humps)

Drop:  90m


Myrddyn Phillips (November 2017)




Sunday, 16 July 2017

Mapping Mountains – Hill Reclassifications – Y Trechol – The Dominant Hills of Wales


Bryn Mawr (SJ 251 190) – Lesser Dominant reclassified to Dominant


There has been a reclassification to the listing of Y Trechol – The Dominant Hills of Wales; resulting in this hill being reclassified from a Lesser Welsh Dominant to a Dominant hill.  With the criteria for inclusion to the Dominant 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 its reclassification was dependent upon a survey with the Trimble GeoXH 6000 which was conducted on the 8th August 2015, with its details appearing in the Carnedd Wen group of hills when published on the Mapping Mountains site on the 3rd June 2017.

Prior to this hill’s inclusion as a Dominant hill it was listed as a Lesser Welsh Dominant hill with 49.13% Dominance based on an estimated c 173m summit height and an estimated bwlch height of c 88m, which gave this hill c 85m of drop.  The bwlch height was later revised to 88m based on the spot height that appears on the Ordnance Survey enlarged mapping hosted on the Geograph website; this revision did not alter this hill’s Dominance value.

The hill is listed in the Carnedd Wen group and is placed in the Region of North Wales (Region A, Sub-Region A4) with its Cardinal Hill being Y Golfa (SJ 182 070), and is situated above the B 4393 road which is to its north and east and the A 483 road to its south-east, and has the Montgomery Canal to its east and the Afon Efyrnwy (River Vyrnwy) to its north, and is positioned between the small communities of Llansantffraid-ym-Mechain to the west north-west, Llanymynech to the north-east, Four Crosses to the east south-east and Ardllin (Arddleen) towards the south.

As the hill is not a part of designated open access land permission to visit should be sought, with the nearest public footpath situated to the north-east of the summit, which consists of overgrown undergrowth and trees.

The name of the hill is Bryn Mawr and it qualifies for Dominant status based on the survey with the Trimble GeoXH 6000 resulting in a summit height of 178.1m (converted to OSGM15) which when coupled with its 88m bwlch spot height gives this hill 90m of drop and 50.53% Dominance.
  

The full details for the hill are:

Group:  Carnedd Wen

Name:  Bryn Mawr

Dominance:  50.53%

OS 1:50,000 map:  126

Summit Grid Reference:  SJ 25117 19054

Summit Height:  178.1m (converted to OSGM15)

Drop Summit to Bwlch:  90m

Drop Bwlch to ODN:  88m 


Bryn Mawr (SJ 251 190) now reclassified to a Dominant hill




Myrddyn Phillips (July 2017)

Thursday, 24 September 2015

Mapping Mountains – Significant Height Revisions – 100m Twmpau and Y Trechol - The Dominant Hills of Wales


Bryn Mawr (SJ 251 190)

There has been a Significant Height Revision to a hill listed in the 100m Twmpau and Y Trechol - The Dominant Hills of Wales, and which was initiated by a survey with the Trimble GeoXH 6000, with these details being retrospective as the survey that resulted in this height revision was conducted on 8th August 2015.

The criteria for the two listings that this height revision affects are:

100m Twmpau - These are the Welsh hills at or above 100m and below 200m in height that have a minimum drop of 30m.  The word Twmpau is an acronym for thirty welsh metre prominences and upward. 

Y Trechol - The Dominant Hills of Wales - These are the Welsh P30 hills whose prominence  equal or exceed half that of their absolute height.

The name of the hill is Bryn Mawr and it is situated in the lower hills of the Carnedd Wen range, and is positioned above the small community of Four Crosses which is situated beside the Afon Efyrnwy (River Vyrnwy) and part of the Montgomeryshire Canal.

The hill was surveyed in the company of Alex Cameron during a multi hill bagging day when the weather was set fine and we visited nine P30 Twmpau hills with seven of them being Trimbled.

Access to Bryn Mawr is good from the west of its summit, as there is sufficient parking close to a gate that accesses a field to another gate which leads on to the hill.  However, the upper section is overgrown and the ancient earthen embankments of its hill fort are now immersed in long grass, nettles and brambles.  The summit is easily identified and the hill is recommended as there is a peaceful ambiance to it.

The hill has a 170m uppermost contour ring on  Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps, with the latter having contour intervals at 5m.  Prior to the survey with the Trimble GeoXH 6000 the hill had been listed with an estimated summit height of c 174m based on the dimensions of the uppermost contour in relation to the steepness of the surrounding ground, with the height resulting from the survey with the Trimble GeoXH 6000 being 178.1m (converted to OSGM15).

Therefore this hill’s new summit height is 178.1m (converted to OSGM15) which is 4.1m higher than its previously estimated height of c 174m and 8.1m higher than its uppermost ring contour on Ordnance Survey 1:50,000 Landranger and 1:25,000 Explorer maps.


The full details for the hill are:

Cardinal Hill:  Carnedd Wen

Summit Height (New Height):  178.1m (converted to OSGM15)

Name:  Bryn Mawr

OS 1:50,000 map:  126

Summit Grid Reference:  SJ 25117 19054
  
Drop:  90m

Dominance:  50.53%


Gathering data from the summit of Bryn Mawr which resulted in this hill's significant height revision


Myrddyn Phillips (September 2015)





Thursday, 3 September 2015

Mapping Mountains – Trimble Surveys – Carnedd Wen


08.08.15  Bryn Mawr (SJ 251 190), Cae Boncyn (SJ 238 193) and Old Oswestry (SJ 295 309)  

Bryn Mawr (SJ 251 190)

Our last three hills of the day started with the delights of Bryn Mawr which is another hill hidden away in the landscape of mid Wales that has an ancient hill fort constructed on it.  This is similar to the first hill we visited earlier in the day; Gaer Fawr Hill (SJ 223 129) as it is now submerged in trees and undergrowth, sometimes this adds to the appeal of such hills as there ancient landscape is hidden and their once proud nature is open to one’s imagination.

We parked to the west of the hill beside a gate that gave access to a covered reservoir, with Alex striding ahead on a freshly mown strip of grass that marched up next to thistle and long grass, this led to a locked gate and barbed wire, which Alex quickly dealt with, with the dexterity of a monkey, whist I crumbled in a heap and struggled Sloth like to its top and perched on a small fence post I then threw myself down to the comparative safety beyond – oh to be young again!

On the path leading to the covered reservoir

Ahead lay swaying grass and a summit swathed in summer growth with the high point beside a tree that had glimpses of the outside sunshine penetrating the canopy above. 

Heading for the summit

As I set the Trimble up on top of my rucksack Alex sat in a patch of sunshine whilst I sneaked away from the equipment and stood beside clumps of nettles and brambles and a multitude of undergrowth.  It was a long wait as the Trimble edged toward the 0.1m accuracy level and eventually I pressed ‘Log’ and waited for it to gather its five minutes of allotted data.

Gathering data at the summit of Bryn Mawr

Alex waiting patiently for the Trimble to do its stuff

My rucksack makes a good improvised tripod

Once the equipment was packed away we found an easier descent route on mown grass to a gate and then through a field which was adjacent to our ascent route, next stop; Gelli Farm and a visit to Cae Boncyn.

The green fields of Cae Boncyn (SJ 238 193)

To get to Gelli Farm Alex navigated us east to the B4393 and then west toward a minor road and a concrete track / road that gains height rapidly up to the farm.  When I parked the farmer was contentedly sunning himself on a reclined seat outside his front door.  I walked toward him, introduced myself and asked if we could visit the hill which was in view from the front of his farm.  He kindly said yes, and directed us to which gates to use and pointed to where the high point was, which was positioned just beyond a bricked construction which looked like a small water tower, I thanked him and re-joined Alex and away we went up the hill.

Heading toward the summit of Cae Boncyn

Alex led through the second gate and a couple of minutes later we were standing on the grassed summit which is to the west of the current position of the 142m spot height on Ordnance Survey maps and in the adjacent field to it.

Away to our south-east was Courthouse Bank (SJ 247 183) and its two distinctive summit ridge trees and beyond was the Breiddin with the quarried western side of the hill bathed in afternoon sunshine.

Looking across to the Breiddin

As the Trimble gathered its data I scribbled a number of notes which are given in the Trimble Survey Spreadsheet on the Spreadsheets heading of this blog, and Alex lazed in the sun admiring the view and happy in life.

Gathering data at the summit of Cae Boncyn

The Trimble on the summit and Alex flat out enjoying the sunshine

Once all the lazing and Trimbling had been completed we retraced our steps back down the hill to the car, before leaving I walked back to the farmer; Mel Jones, and thanked him once again for letting us visit the hill, I also asked if he knew of a name for it and indeed he did as he quickly said ‘we call it Cae Boncyn which is the name of the field’.  He then mentioned the ‘Rabbit Field’, the ‘Maes’ and the ‘Barracks’, all are individual bounded fields either on Mel’s land or adjacent to it.

As the conversation continued with Mel, he said ‘hang on a moment’ and disappeared in to his house and reappeared a couple of minutes later with a large back-boarded map of his farm.  This was made by his father and passed down to Mel and will, sometime in the future, be passed down to Mel’s sons.  On the map was each field with their name written against them, with the field where the 142m spot height is positioned on current maps being named the ‘Top Field’ and the field where the high point of the hill is situated and where the Trimble had been placed named as ‘Cae Boncyn.’

I asked Mel if I could take some photos of him with the map and we stood on his lawn, beside his farm with him proudly holding the map.  It was great meeting Mel and talking about his farm and the various names written on the map; if only every farmer had such a thing as then the preservation of locally known place-names would be made much easier.

Mel Jones with the Gelli Farm field map

The map has each individual field named with the high point of the hill named as Cae Boncyn

Only one hill remained and that was positioned across the border in deepest, darkest England on the outskirts of Oswestry.  The name of our last hill is Old Oswestry, to my knowledge the hill doesn’t appear in any hill list but we thought it stood an outside chance of becoming a new Tump.

Old Oswestry is positioned on the northern outskirts of the town that bears part of its name and can be easily accessed from a visitor car park to its west.  This gives immediate access to its impressive earthen ramparts and its upper section.  The area of this ancient hill fort is now in the guardianship of English Heritage and it was classified as a Scheduled Monument in 1997.

An artist's impression of Old Oswestry

Old Oswestry is one of the best preserved hill forts in the country and has five sets of ramparts enclosing a central area of 8.4 hectares.  As we walked up the path past these ramparts a number of people were sitting in the sun after having visited the site.  Nearing the top we found the central section with its high point being lazily guarded by a herd of cows that were contentedly munching on grass whilst the labours of the world passed them by.

Looking past one of the series of earthen ramparts onto summer activity below

We walked part of the upper rampart and then visited the central cow pasture where we picked the spot for Trimble placement and sat in the sun as it gathered its five minutes of data.  During this time a friendly cow visited us and slowly edged itself ever nearer, it was an inquisitive beast and I hoped its attention would be kept on Alex in preference to a sticky slurping lick of a brightly coloured Trimble that was positioned on the ground a few metres from it.

Making friends

Gathering data at the summit of Old Oswestry

Once the Trimble was safely packed away we headed back to the car and drove to Gobowen for Alex to catch the train back home.  It had been a great couple of days with Alex visiting Yr Allt yesterday and a good bagging day today, all that remained was to write a multitude of blog posts and process a multitude of data!

Alex catching the train back home

Survey Result:


Bryn Mawr

Summit Height:  178.1m (converted to OSGM15) (significant height revision)

Summit Grid Reference:  SJ 25117 19054

Drop:  90m (Subhump addition confirmed)

Dominance:  50.53% (Lesser Dominant reclassified to Dominant confirmed)





Summit Height:  142.1m (converted to OSGM15)

Summit Grid Reference:  SJ 23849 19306 (summit relocation confirmed)

Drop:  44m

Dominance:  30.97%




Old Oswestry

Summit Height:  165.1m (converted to OSGM15)

Summit Grid Reference:  SJ 29533 30990

Drop:  c 27m

Dominance:  16.35%




For further details please consult the Trimble survey spreadsheet click {here}