Monday 30 April 2018

Mapping Mountains – Hill Reclassifications – Y Pellennig – The Remotest Hills of Wales


Tap Llwyd (SH 719 065) – Pellennig addition

There has been an addition to the listing of Y Pellennig – The Remotest Hills of Wales due to a survey with the Trimble GeoXH 6000 that was instigated by a previous basic levelling survey (BLS) and summit and bwlch spot heights that appear on the Ordnance Survey Interactive Coverage Map hosted on the Geograph website. 

The criteria for qualification as a Pellennig is any Welsh hill whose summit is at least 2.5km from the nearest paved public road and the hill has a minimum 15m of drop, the list is a joint compilation between Myrddyn Phillips and Aled Williams and is available as a downloadable e-booklet or print-booklet version on Mapping Mountains Publications with the up-to-date master list available on the Mapping Mountains site in Google Doc format.

Tap Llwyd (SH 719 065)

The name of the hill is Tap Llwyd and prior to the Trimble GeoXH 6000 survey this hill was not classified as it had been surveyed on the 29.09.05 by Myrddyn Phillips using the BLS method as having 44ft 6̋ / 13.6m of drop.  Importantly on this day only the high point of the hill outside of its adjacent conifer plantation could be taken as its summit.  Since the BLS was conducted the Ordnance Survey Interactive Coverage Map hosted on the Geograph website has become available, and this map gives this hill 15m of drop with a 566m summit and 551m bwlch spot height.

The hill is situated in the Tarennydd group of hills with its Cardinal Hill being Tarren y Gesail (SH 710 058) and is placed in the Region of North Wales (Region A, Sub-Region A3).  The hill is positioned between the A 487 road to its east and the B 4405 road to its west and has the small community of Abergynolwyn towards its west, and has conifer plantations surrounding its western slopes and its lower eastern slopes.

As the designated border of open access land only takes in the open hillside and not the conifer plantation to the hill’s immediate west, permission to visit its summit should be sought, however common sense should prevail and as its high point is only a few metres in to what was felled forestry at the time of the Trimble survey, it is likely there would be no objection to its summit being visited.

Two points were surveyed with the Trimble GeoXH 6000 for summit position, the first being the high point of the hill outside the forestry and the second being the high point of the hill in what on the day of the survey was felled forestry, these surveys came to; 564.7m (converted to OSGM15) and 565.7m (converted to OSGM15) respectively, and with a bwlch height of 550.5m (converted to OSGM15), these values give this hill 15.3m of drop, and as the nearest paved public road is 2.875km from the summit of Tap Llwyd this hill meets the criteria for inclusion as a Pellennig hill.

The Trimble GeoXH 6000 gathering data at the summit of Tap Llwyd

The full details for the hill are:

Cardinal Hill:  Tarren y Gesail

Summit Height:  565.7m (converted to OSGM15)

Name:  Tap Llwyd

OS 1:50,000 map:  124

Summit Grid Reference:  SH 71990 06571 
  
Drop:  15.3m (converted to OSGM15)

Remoteness:  2.875km


For the additions and deletions to Y Pellennig – The Remotest Hills of Wales reported on Mapping Mountains please consult the following Change Register:







Sunday 29 April 2018

Mapping Mountains – Hill Reclassifications – Yr Uchafion


Tap Llwyd (SH 719 065) – Uchaf addition

There has been an addition to the listing of Yr Uchafion due to a survey with the Trimble GeoXH 6000 that was instigated by a previous basic levelling survey (BLS) and summit and bwlch spot heights that appear on the Ordnance Survey Interactive Coverage Map hosted on the Geograph website.  

Yr Uchafion is the draft title for a list of the Welsh 500m P15s that takes in all hills in Wales at or above 500m in height that have a minimum drop of 15m, the list is a joint compilation between Myrddyn Phillips and Aled Williams with the introduction to the list being published on Mapping Mountains in November 2015.

Tap Llwyd (SH 719 065)

The name of the hill is Tap Llwyd and prior to the Trimble GeoXH 6000 survey this hill was not classified as it had been surveyed on the 29.09.05 by Myrddyn Phillips using the BLS method as having 44ft 6̋ / 13.6m of drop.  Importantly on this day only the high point of the hill outside of its adjacent conifer plantation could be taken as its summit.  Since the BLS was conducted the Ordnance Survey Interactive Coverage Map hosted on the Geograph website has become available, and this map gives this hill 15m of drop with a 566m summit and 551m bwlch spot height.

Extract from the Ordnance Survey Interactive Coverage Map hosted on the Geograph website

The hill is situated in the Tarennydd group of hills with its Cardinal Hill being Tarren y Gesail (SH 710 058) and is placed in the Region of North Wales (Region A, Sub-Region A3).  The hill is positioned between the A 487 road to its east and the B 4405 road to its west and has the small community of Abergynolwyn towards its west, and has conifer plantations surrounding its western slopes and its lower eastern slopes.

As the designated border of open access land only takes in the open hillside and not the conifer plantation to the hill’s immediate west, permission to visit its summit should be sought, however common sense should prevail and as its high point is only a few metres in to what was felled forestry at the time of the Trimble survey, it is likely there would be no objection to its summit being visited.

Two points were surveyed with the Trimble GeoXH 6000 for summit position, the first being the high point of the hill outside of the forestry and the second being the high point of the hill in what was felled forestry, these surveys came to; 564.7m (converted to OSGM15) and 565.7m (converted to OSGM15) respectively, and with a bwlch height of 550.5m (converted to OSGM15), these values give this hill 15.3m of drop, which is sufficient for it to qualify for Uchaf status.

Gathering data with the Trimble GeoXH 6000 at the summit of Tap Llwyd

The full details for the hill are:

Cardinal Hill:  Tarren y Gesail

Summit Height:  565.7m (converted to OSGM15)

Name:  Tap Llwyd

OS 1:50,000 map:  124

Summit Grid Reference:  SH 71990 06571  
 
Drop:  15.3m (converted to OSGM15)


For the additions, deletions and reclassifications to Yr Uchafion / The Welsh 500m P15s reported on Mapping Mountains please consult the following Change Registers:










For details on the survey that confirmed this hill's addition as an Uchaf

Myrddyn Phillips and Aled Williams (April 2018)


Saturday 28 April 2018

Mapping Mountains – Trimble Surveys – Tarennydd



01.04.18  Graig Goch (SH 714 084), Tarren Cadian (SH 729 072), Tap Llwyd (SH 719 065), Tarren y Gesail (SH 710 058) and Graig Wen (SH 694 068)

Graig Goch (SH 714 084)

The hills of the Tarennydd are like forgotten beasts nestled as they do against their higher and more dramatic neighbour of Cadair Idris.  Their slopes and ridges have been ravaged by man, with many now swamped in regimented conifer plantations and higher cymoedd dug deep with old mine workings.  However, they do have a peaceful charm, one where few people tread.

The circuit of Glyn Iago was suggested by Aled, who I met in Abergynolwyn at 8.30am on Easter Sunday, with the previous day damp and grey and the next forecast for heavy, persistent rain, we had chosen wisely as an early morning chill pervaded the land with edges of blue sky and a forecast of dry overhead conditions.

Having left one car in Abergynolwyn we drove toward the farm of Rugog and left the other in a large lay-by on the A 487.  This enabled an ascent of Graig Goch via its north-eastern slopes on a gauged out track that meanders its way up the hill from the aforementioned farm.  On our way we called at the farm to make place-name enquiries and were met by a number of barking dogs and one of the two occupants appearing in her dressing gown, after a cordial chat and permission to use the track we set off uphill.

As height was gained the bulk of Cadair Idris with its snow-capped slopes bulged in to view, a dramatic scene dominating the western view, ahead lay the upper reaches of Cwm Dylluan and the large conifer plantation that takes in much of the lower slopes of these hills, however much of the upper section of trees had been felled which would help in connecting Graig Goch with Tarren y Gesail and hopefully with a number of surveys that were planned for the day ahead.

Cadair Idris

The felled forestry leading from Graig Goch to Tarren Cadian

The track petered out near the summit of Graig Goch with a narrow path leading toward the hill’s high point, as I set the Trimble up Aled headed off to investigate the western slopes which plunged down in a dizzying way to the watered calm of Tal y Llyn below.

Gathering data at the summit of Graig Goch

Dizzying views down to Tal y Llyn

Cadair Idris and Tal y Llyn

Leaving the summit we back-tracked toward the end of the track before venturing in to the felled forestry which quickly brought us down to the connecting bwlch which consisted of a T-junction forest track, and once five minutes of data were collected with the Trimble we headed up a zig-zagging bulldozed narrowing track that led up toward the connecting north-easterly ridge of Tarren y Gesail where two hills were positioned that were going to be Trimbled.

At the bwlch of Graig Goch

The felled forestry beyond the end of the narrow bulldozed track

The going on the ridge consisted of moorland tussocks with a slight path of sorts leading beside the ridge fence toward the high point of Tarren Cadian, a 597m map heighted hill whose summit peered out on more conifer plantation to the south-east.

On the ridge leading to Tarren Cadian

Aled heading for the summit of Tarren Cadian

Two tussocked hummocks vied for the high point of the hill, we used an improvised method of levelling to determine the higher and once the Trimble had gathered its allotted data we set off on the continuation of the ridge down toward the connecting bwlch which we judged to be positioned amongst the conifers, this was Trimbled before we excavated ourselves from the trees and headed up toward Tap Llwyd.

Gathering data at the summit of Tarren Cadian

Not the best place for a survey

This next hill is given 15m of drop on the Ordnance Survey Interactive Coverage Map hosted on the Geograph website, and with a summit over 500m in height, it should, according to these figures qualify for Uchaf status.  However, I surveyed this hill in September 2005 as having 44ft 6˝ / 13.6m of drop, on that day I could only survey the high point of the hill that remained out of the conifer plantation and with no knowledge of the spot heights that would later appear on the Geograph map I was satisfied that this hill was not an Uchaf.  But today we found the forestry felled which gave the opportunity to survey two points for the summit and two for the bwlch position.

Gathering data at the high point outside of the felled forestry

The first potential summit point to be surveyed was beside the ridge fence, the second was amongst the debris of felled trees, on ground laid waste by the blight of conifers.  These were followed by the bwlch with two points surveyed to ground at the base of the ridge fence.  Happy with our efforts we plodded on.

Following the ridge fence toward the high point in the felled forestry with Tarren y Gesail in the bcakground

Gathering data at the summit of Tap Llwyd

Gathering data at one of two positions surveyed for the bwlch position of Tap Llwyd

The next part of the walk consisted of putting your head down and plodding uphill and in the process gaining about 110m of height toward the connecting fence to the trig pillar atop Tarren y Gesail.  As Aled munched on a sandwich beside the small wind shelter next to the trig I set the Trimble to gather data amongst a sea of tussocks, any of which could have laid claim to being the summit.  Aled then investigated the high land of tussocks and suggested a second data set was taken nearer the trig, once this was done we headed down toward a forest break that led to a forest track which headed toward our last hill of the day; Graig Wen.

Looking back toward Tap Llwyd and Tarren Cadian

Pick your tussock - gathering data at the summit of Tarren y Gesail

The forest track conveniently passed over this hill’s connecting bwlch which was Trimbled and then followed a slow plod uphill leading to the summit of Graig Wen.

Gathering data at the critical bwlch of Graig Wen

By now the wind had increased in strength and the cloud had caused a milky sun which heralded the incoming weather front that would soak the land the following day, thankfully we remained dry for the nine hours that we were on the hill.

The summit of Graig Wen consists of an attractive rocky knoll and as the Trimble gathered data I sat with Aled trying to shelter from the chilled wind.  Once data were stored and the Trimbke closed down and packed away we headed down toward the high dead end paved road leading to the old Bryn Eglwys Quarry.

Gathering data at the summit of Graig Wen

The paved road is steep in places but gave a relatively quick descent to the awaiting car parked in Abergynolwyn.  It had been another good day on the hill with five hills surveyed and a new Pedwar in Graig Wen bagged, and with new land covered connecting Graig Wen with Tarren y Gesail.

  

Survey Result:


Graig Goch

Summit Height:  585.6m (converted to OSGM15)

Summit Grid Reference:  SH 71479 08459

Bwlch Height:  455.9m (converted to OSGM15)

Bwlch Grid Reference:  SH 72601 08269

Drop:  129.7m

Dominance:  22.14%





Tarren Cadian

Summit Height:  598.1m (converted to OSGM15)

Summit Grid Reference:  SH 72947 07296

Bwlch Height:  529.4m (converted to OSGM15)

Bwlch Grid Reference:  SH 72369 06752

Drop:  68.7m

Dominance:  11.48%





Tap Llwyd

Summit Height:  565.7m (converted to OSGM15)

Summit Grid Reference:  SH 71990 06571

Bwlch Height:  550.5m (converted to OSGM15)

Bwlch Grid Reference:  SH 71857 06414


Dominance:  2.70%

Remoteness:  2.875km (Pellennig addition confirmed)





Tarren y Gesail

Summit Height:  666.5m (converted to OSGM15)

Summit Grid Reference:  SH 71031 05890

Bwlch Height:  201.2m (LIDAR)

Bwlch Grid Reference:  SH 73733 09375 (LIDAR)

Drop:  465.3m (Trimble summit and LIDAR bwlch)

Dominance:  69.81%






Summit Height:  454.1m (converted to OSGM15)

Summit Grid Reference:  SH 69405 06806

Bwlch Height:  367.5m (converted to OSGM15)

Bwlch Grid Reference:  SH 69874 06631

Drop:  86.7m

Dominance:  19.08%






Friday 27 April 2018

Mapping Mountains – Trimble Surveys – Brown Clee Hill



26.03.18  Brown Clee Hill (SO 593 867)

Brown Clee Hill (SO 593 867)

I’ve lived in border country all my life, that haphazard delineating line between Wales and England with my forbears and myself rooted in the formers land.  Across the border lies the English county of Shropshire which in the main is topographically a part of greater Cambria, however until recent times I had not investigated the Shropshire hills, this has been rectified over recent years and their appeal and also variety is great, but the highest hill of the county until today had evaded me.

The county high point of Shropshire is Brown Clee Hill which is given a 540m map height and is adorned with a number of heathery bumps on its summit area, one of which has a topographic viewfinder standing on a levelled plinth with the customary stone steps leading up to it, whilst there are also two large radar masts near the high point.  Although it is the topographic viewfinder that acts as a honeypot for most walkers this is not the summit of the hill, the high point is a little further north on one of the heathery mounds beside the radar compound.

By the time I parked the chilled air of early morning had been swept away and spring’s warmth cascaded down from a radiant blue sky.  This first hill warmth is always an awakening experience when winter’s harsh climate and its sometimes oppressive day light hour’s gives way to burgeoning growth with greenery sprouting and welcoming lushness.

I had planned to use the paved access track to the radar masts as my ascent route but decided to park next to other cars in a large lay-by adjacent to a public footpath giving access through the Stanbroughs Wood on the eastern part of the hill.  I was thankful I did so, as the wood proved a welcome release from what would have been a strip of tarmac, it also proved rather beautiful with mixed woodland and a good, albeit muddy path leading forever upward.

The route to Brown Clee Hill from the east

The path broke out of the forestry through a gate on to open hillside and soon the remains of the Abdon Quarry came in to view with a large derelict building nestled against the upper easterly slopes of the hill, beyond was the paved access track and the two large radar masts, and above was blue sky, which proved a pleasing quality detracting from man’s imposition on the hill.

Derelict buildings from the old Abdon Quarry

The paved road leading to the radar masts

The paved track led to the plinth and panoramic viewfinder where a number of people were quietly taking in the view, I continued toward the heathery mound where the summit of the hill is positioned, once there I quickly assembled the Trimble atop my rucksack giving it elevation above its immediate surrounds and which acts as an improvised tripod.

Gathering data at the summit of Brown Clee Hill

As the Trimble beeped away gathering its allotted data I stood back and took in the view, it was good to be out on the hill in such beautiful weather.  If the viewfinder position was quiet I also wanted to gather data from its immediate periphery, and by the time data were stored from the high point all walkers had left, so I headed back to the plinth and gathered a further two data sets, one from the high point beside the stone façade of the plinth and the other from an embedded rock which visually was slightly higher, during this three other walkers appeared, one from the west and the other two from the route I had taken from the east, I chatted with all and explained what I was doing.

Gathering data at the edge of the viewfinder plinth

Gathering data on an embedded rock close to the viewfinder plinth

After data were stored and the Trimble packed away I retraced my inward route back to my car.   

LIDAR col image of Brown Clee Hill

Postscript:

Since the summit survey of this hill full LIDAR coverage is now available.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height and positional data that is now freely available for England and Wales.  Consequently the numerical details for this hill have been analysed using this technique, resulting in the LIDAR height and position for its col being used.

 


Survey Result:



Brown Clee Hill

Summit Height:  540.5m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SO 59372 86701 (Trimble GeoXH 6000)

Col Height:  165.9m (LIDAR)

Col Grid Reference:  SO 61034 94666 (LIDAR)

Drop:  374.5m (Trimble GeoXH 6000 summit and LIDAR col)

Dominance:  69.30% (Trimble GeoXH 6000 summit and LIDAR col)