Tuesday, 25 July 2017

Mapping Mountains – Significant Name Changes – Y Trichant

Commins (SJ 174 282)

This is the seventy eighth post under the heading of Significant Name Changes, and the following details are in respect of a hill that was surveyed with the Trimble GeoXH 6000 on the 7th June 2017.

The hill is a part of the Y Berwyn group of hills, which is situated in the south-eastern part of North Wales (Region A, Sub-Region A4), and is positioned above the small community of Llansilin which is to the east of the hill. 

Commins (SJ 174 282) with Gurn Moelfre behind

The hill appeared in the sub list adjoined to the 300m P30 list on Geoff Crowder’s v-g.me website under the partly invented name of Pen-y-Moelfre, with an accompanying note stating; Name from village to the East.  The listing this hill is now a part of is named Y Trichant and these are the 300m height band of hills within the Twmpau (thirty welsh metre prominences and upward) and its summit height, drop and status was confirmed by a survey with the Trimble GeoXH 6000.  

Pen-y-Moelfre    376m    SJ175282    125255    Name from village to the East

During my early hill listing I thought it appropriate to either invent a name for a hill, or use a name that appeared near to the summit of the hill on Ordnance Survey maps of the day.  My preference was to use farm names and put Pen, Bryn or Moel in front of them.  This is not a practice that I now advocate as with time and inclination place-name data can be improved either by asking local people or by examining historical documents, through this form of research an appropriate name for the hill can usually be found, and in the case of this hill it was one of the local farmers who has lived under the hill all of his life who gave the name of the Commins.

Emyr Evans

The local farmer is Emyr Evans who farms from Cefn-y-braich which is situated towards the east south-east of the hill.  Emyr is now aged 81 and has lived locally for all of his life; he told me that the hill is a part of the land of Lloran Isaf which is the next farm along from Cefn-y-braich and nearer to the hill.  Emyr was out cutting thistles and we chatted at length, it turns out that Emyr went to school with an uncle of one of my lifelong friends and before leaving he told me that there used to be a flagpole on top of the hill.

Therefore the name this hill is now listed by in the Y Trichant and the Twmpau is the Commins and this name was derived from local enquiry. 

The full details for the hill are:

Group:  Y Berwyn

Name:  Commins

Previously Listed Name:  Pen-y-Moelfre 

Summit Height:  376.1m (converted to OSGM15)

OS 1:50,000 map:  125

Summit Grid Reference:  SJ 17476 28210 
Drop:  34.7m (converted to OSGM15)

Myrddyn Phillips (July 2017)

Monday, 24 July 2017

Mapping Mountains – Trimble Surveys – Y Berwyn

07.06.17  Commins (SJ 174 282), Moel y Gwelltyn (SJ 170 277), Ffridd Fawr (SJ 166 274) and Moel Lloran (SJ 154 279)

Moel y Gwelltyn (SJ 170 277)

These hills form a compact group to the north-east of Llanrhaeadr-ym-Mochnant and proved the ideal chose for a day when rain was predicted late in the afternoon.  I had my boots on and walking by 7.35am and followed the continuation of the narrow lane east past the farm of Oddi-ar-y-llyn before cutting up on a track that headed toward Ceunant-du.  I followed the track for a short while, leaving it to slowly plod up grassed slopes where sheep were lazing away still asleep.

The ever present profile of Gurn Moelfre dominated the view, a great sweep of a hill with its western side inviting an ascent; it’s a hill that I’ve only visited once and one that I may leave for the completion of my second round of Welsh Deweys.

As I headed up to the first summit of the day a keen breeze whipped across the hill, I quickly put on a thin outer shell and continued to the high point, which consists of a small grassed area with expansive views.  Judging the position of the summit was relatively easy and once the Trimble was placed on the ground and gathering data I looked out toward Gurn Moelfre and the countryside beyond, all seemingly quiet and breeze blown.

Gathering data at the summit of the Commins

Moel y Gwelltyn from the Commins

Once five minutes of data were stored I headed down to the connecting bwlch between this hill and its higher neighbour of Moel y Gwelltyn, approaching this bwlch from such a vantage point proved advantageous as it gave a view of where the valley to valley traverse met and the probable point for the critical bwlch.  As I sauntered down the slope toward the bwlch a tractor chugged round the slope on a green track, I flagged it down and spent a number of minutes chatting with Emyr Evans, who farms from Cefn-y-braich.  Emyr is aged 81 and has lived in this area all his life and went to school with the uncle of one of my good friends, he told me that the hill I had just come down and which was directly above us is known as the Commins. 

Emyr Evans

Leaving Emyr to head off to cut thistles I set the Trimble up at the connecting bwlch for another data set, before heading up to the summit of Moel y Gwelltyn; the high point of my day.  This proved a lovely hill, with its summit enclosed with Scots Pine and radiant this morning as the sun cast warmth after the slight wind-blown chill encountered on the summit of Commins.

Gathering data at the critical bwlch of the Commins

The Trimble has been operating well over recent months and seems to be able to pick up sufficient satellite coverage relatively quickly even when placed in an enclosed area, and within a couple of minutes the required 0.1m accuracy level had been attained before data should be logged and it was beeping away gathering datum points perched on top of my rucksack, which is used as an improvised tripod to give it elevation above its immediate surrounds.

Gathering data at the summit of Moel y Gwelltyn

Gurn Moelfre from Moel y Gwelltyn

The survey of the bwlch and summit of my next planned hill would confirm its status as it is currently listed as a Sub-Trichant having not appeared in the sub list that accompanied the Welsh P30 hills when published on Geoff Crowder’s v-g.me website.  According to the map the critical bwlch for this sub hill is placed on or near a track that heads toward Tyddyn Maen, I hoped the relatively early hour would mean that this house was still quiet as having someone pottering about with an unusual yellow and black piece of equipment set up on top of a rucksack and left for five minutes or so whilst the person operating it scampers off a safe distance away can sometimes look unusual, and perhaps also unwelcome.  Thankfully all was quiet and once five minutes of data were stored I packed the equipment away and headed up a track toward the grassed slopes above.

Gathering data at the critical bwlch of Ffridd Fawr

The track soon gave out and as I headed up the continuation of a grazing field toward its high point a quad bike whizzed about in front, I waved and headed over for a chat; Edgar Williams farms from Bronheulog and told me that the hill is known as Ffridd Fawr, and it is as its name suggests; a large upland pasture.  We chatted for a number of minutes and I thought how lucky I’d been as with four hills planned to visit and with two of these unnamed on the map, the two farmers who I’d met were both on these unnamed map hills.

Edgar Williams

As Edgar sped off I headed toward where the 335m spot height appears on the map and proceeded to gather another five minute data set, I then back tracked across the summit ridge to another high point amongst gorse bushes to gather a second data set.  As the Trimble gathered data from these two points Moel y Gwelltyn stood sublime above, with its great wooded conical shaped profile on grand display.

Gathering data at the summit of Ffridd Fawr

Gathering data at the second high point of Ffridd Fawr

By now the warmth of the late morning had dispersed the chilled breeze and I followed the track down from Tyddyn Maen to the narrow lane that I’d driven down earlier in the morning.  Following this lane south brought me to a T-junction and soon afterward a gate which gave access to the lower slopes of my last hill of the day; Moel Lloran.

The view west

I slowly plodded up the greened and grazed slopes toward the summit of Moel Lloran and soon had the Trimble set up gathering data as the breeze blew and the world below shot down steeply toward a seemingly ever expanding view of hill after hill, a beautiful site within quiet and peaceful surrounds.

The south-eastern slopes of Moel Lloran

Gathering data at the summit of Moel Lloran

Leaving the summit I encountered barbed wire fences and steep Hawthorne hedges before finding an access gate that took me over another narrow lane to a public footpath positioned near to the critical bwlch of Moel Lloran, as a number of cattle were inquisitively looking my way I approached this bwlch slowly and proceeded to assess the lay of ground before placing the Trimble atop my rucksack for its five minutes of allotted data, during this I remained still and quiet as did the cows.

Gathering data at the critical bwlch of Moel Lloran

Just one data set remained and that was placed close to where I had parked my car, getting there involved finding a public footpath through long grass, a farm yard and across a couple of fields, once there I assessed the lay of land and placed the Trimble on top of my rucksack beside a hedge and waited for the last of the day’s data sets to be gathered.

Gathering data at the critical bwlch of Moel y Gwelltyn

When combined these four hills had proved an ideal way to spend a few hours amongst quiet surrounds, with the added bonus of meeting two farmers and recording names for the two hills that remain unnamed on current Ordnance Survey maps. 

Survey Result:

Summit Height:  376.1m (converted to OSGM15)  

Summit Grid Reference:  SJ 17476 28210

Bwlch Height:  341.4m (converted to OSGM15)

Bwlch Grid Reference:  SJ 17370 27991

Drop:  34.7m (Trichant status confirmed)

Dominance:  9.23%

Moel y Gwelltyn

Summit Height:  382.8m (converted to OSGM15) 
Summit Grid Reference:  SJ 17036 27782

Bwlch Height:  238.8m (converted to OSGM15)

Bwlch Grid Reference:  SJ 16396 28185

Drop:  144.0m (Submarilyn status confirmed)

Dominance:  37.62% (Lesser Dominant status confirmed)

Ffridd Fawr (significant name change)

Summit Height:  335.1m (converted to OSGM15) 
Summit Grid Reference:  SJ 16688 27439

Bwlch Height:  312.4m (converted to OSGM15)

Bwlch Grid Reference:  SJ 17003 27548

Drop:  22.7m (Sub-Trichant addition confirmed)

Dominance:  6.77%

Moel Lloran

Summit Height:  297.2m (converted to OSGM15) (200m Twmpau status confirmed)  

Summit Grid Reference:  SJ 15401 27907

Bwlch Height:  257.4m (converted to OSGM15)

Bwlch Grid Reference:  SJ 15676 28447

Drop:  39.7m

Dominance:  13.37%

Sunday, 23 July 2017

Mapping Mountains – Trimble Surveys – Moel Hebog

04.06.17  Moel Tryfan (SH 517 559) and Moel Tryfan (SH 515 561)

Moel Tryfan (SH 515 561)

Moel Tryfan stands as the north-western outlier of the higher Mynydd Mawr, and is designated a site of special scientific interest  and is one of the most important places in the country to examine geology, as in many places the rocks have been exposed due to quarrying activities that have resulted in the upper part of the hill being split in two, with the south-easterly part lower, it is also this lower part of the hill that Aled analysed via LIDAR data and through this a new 400m Sub-Pedwar has been listed, as in affect the quarry has created a north and south bwlch between the two tops with the land between having been ripped apart, leaving a gaping hole.

My plan was to survey each summit and bylchau and compare the Trimble data with that produced by LIDAR and also that produced for the higher summit by the survey with the Leica GS15 which was conducted in July 2013.

Access to the hill from the south is easy as a paved road that turns into a gravelled track leads from the last few houses east of Y Fron.  As I walked up the track a runner sped down, we stopped and chatted and she told me that the gun club were firing just below the summit, I appreciated hearing this as otherwise the sound of gunfire may have proved a little disconcerting.

Away to the south grey cloud was already massing around the higher peaks and with a forecast of heavy showers in the central part of the country I hoped that I’d picked a good and dry place to walk today.

Approaching Moel Tryfan

The track I was on headed toward the southern bwlch which is the higher and critical bwlch for the 400m Sub-Pedwar, the view north was down to exposed quarry lakes and the hills beyond.  I used the Trimble as a hand-held GPS and zeroed in to the grid reference produced by Aled’s LIDAR analysis, I’ve learnt to have confidence in these positions as LIDAR is proving a revolutionary tool for positions and heights associated with hills.

Once the Trimble was set up and gathering data I walked down the track to gain a better view of the 400m Sub-Pedwar, the whole of its western face was now exposed, having been ripped apart leaving an extended cliff and waste spoil of rubble.

Gathering data at the critical bwlch of Moel Tryfan (SH 517 559)

Moel Tryfan (SH 517 559) the recent addition to the 400m Sub-Pedwarau

Packing the Trimble away a narrow path led across a flat rubbled land bridge and continued toward the summit, which proved to be the second high point amongst heather overlooking a large drop to the quarry lakes below.

When surveying with John and Graham one of the most enjoyable times for me was the wait during data collection, this was a time to talk, but also a time to watch the landscape in all its moods as light appeared and shadow cast down, and although the timeframe  surveying with the Trimble is very different as five minutes of data gives accurate results, this waiting process is still one where I stand and look and appreciate the surroundings, and whilst the Trimble gathered its allotted summit data I looked out to the rock outcrop atop the higher of the two Moel Tryfan summits and down into the great gash of the quarry, which is now a peaceful place where once man’s activities coursed the whole eastern part of the upper section of this hill to be ripped apart.

Gathering data at the summit of Moel Tryfan (SH 517 559)

The Trimble set-up position at the summit of Moel Tryfan (SH 517 559)

Leaving the lower summit I soon joined another track leading to the northern bwlch, and again the ten figure grid reference produced by LIDAR took me to the point for the Trimble set-up position.  As the Trimble gathered data the sky turned deep grey and a few wind-blown raindrops sped across the hill, not wanting to linger I quickly closed the equipment off after it had gathered five minutes of data and headed up to the main summit on a rutted and earthen track before a grassed path led to the rock outcrop at the top.

Gathering data at the lower northern bwlch

The rock outcrop at the summit of Moel Tryfan (SH 515 561)

An information board is pinned to the lower face of the rock outcrop and states that on Sunday 26th June 1842 Charles Darwin stood on the summit of Moel Tryfan and studied its rock formations.  Today the summit was quiet, except for the Trimble beeping away gathering datum points perched on the high point of the hill and wedged in place with two small retaining rocks that I’d brought for this specific purpose.

The information board pinned to the rock outcrop

As the Trimble gathered data I busied myself writing down all required information and taking a number of photos, once the equipment was closed off and packed away I followed a path down to the southern bwlch and retraced my inward route back to the car.

The summit of the higher of the two Moel Tryfan peaks with the Trimble gathering data perched on top of the rock outcrop

The Trimble set-up position at the summit of Moel Tryfan (SH 515 561)

Looking across Dyffryn Nantlle to Y Garn

Survey Result:

Moel Tryfan

Summit Height:  405.4m (converted to OSGM15) 
Summit Grid Reference:  SH 51780 55926

Bwlch Height:  384.0m (converted to OSGM15)

Bwlch Grid Reference:  SH 51522 55908

Dominance:  5.28%

Moel Tryfan

Summit Height:  428.9m (converted to OSGM15, Trimble GeoXH 6000) 429.0m (converted to OSGM15, Leica GS15)  
Summit Grid Reference:  SH 51528 56190

Drop:  102.6m (converted to OSGM15, Leica GS15 summit and bwlch)

Dominance:  23.92%

Saturday, 22 July 2017

Mapping Mountains – Hill Reclassifications – Y Pedwarau

Pt. 389.3m (SN 952 552) – 390m Sub-Pedwar deletion

There has been a deletion to the listing of Y Pedwarau due to analysis of LIDAR data by Aled Williams.  Y Pedwarau is the title for the list of 400m hills of Wales and takes in all Welsh hills at or above 400m and below 500m in height that have a minimum 30m of drop, the list is a joint compilation between Myrddyn Phillips and Aled Williams and it commenced publication on Mapping Mountains on the 30.01.17.

Accompanying the main Y Pedwarau list are five categories of sub hills, with this hill being deleted from the 390m Sub-Pedwar categoryThe criteria for 390m Sub-Pedwar status being all Welsh hills at or above 390m and below 400m in height that have a minimum 30m of drop.

Prior to analysis of LIDAR data the hill was listed with 76m of drop based on the 390m summit spot height that appears on the Ordnance Survey 1:25,000 Explorer map and the 314m bwlch spot height that appears on the Ordnance Survey enlarged mapping hosted on the Geograph website.

The hill is situated in the Elenydd range with its Cardinal Hill being Gorllwyn (SN 917 590) and is placed in the Region of Mid and West Wales (Region B, Sub-Region B2), the hill is positioned between the small communities of Llanafan Fawr to the east north-east and Glandulas towards the south.

As the hill is not a part of designated open access land permission to visit should be sought, if permission is granted there are public footpaths that approach the hill from the north, west and south.

The hill is being listed by the point (Pt. 389.3m) notation as the authors do not know an appropriate name for it either from local enquiry or from historical research, and its deletion from 390m Sub-Pedwar status is due to the analysis of LIDAR data by Aled Williams.  LIDAR (Light Detection & Ranging) is highly accurate height data that is now freely available for much of England and Wales.

Aled’s analysis of LIDAR data gives the hill the following details:

Pt. 389.3m

Summit Height:  389.3m

Summit Grid Reference:  SN 95203 55201

Bwlch Height:  314.4m

Bwlch Grid Reference:  SN 95556 55887

Drop:  74.9m

Therefore, the 389.3m LIDAR data produced for the summit position at SN 95203 55201 and the 314.4m LIDAR data produced for the bwlch position at SN 95556 55887 gives this hill 74.9m of drop and with its summit height being below 390m it is insufficient for its continued inclusion as a 390m Sub-Pedwar.

The full details for the hill are:

Cardinal Hill:  Gorllwyn

Summit Height:  389.3m (LIDAR data)

Name:  Pt. 389.3m

OS 1:50,000 map:  147

Summit Grid Reference:  SN 95203 55201

Drop:  74.9m (LIDAR data)

The total for Y Pedwarau remains at 442 hills with nine additions, and fourteen reclassifications to 400m Sub-Pedwar status since publication of the list by Europeaklist in May 2013.

The total for the 390m Sub-Pedwarau decreases by one to 37 hills and the total for the 390m Double Sub-Pedwarau remains at 26 hills.

The list of Pedwar hills is available from the Haroldstreet website (January 2014) with all subsequent changes detailed on the Mapping Mountains site, with the list also having commenced publication on Mapping Mountains on the 30.01.17.

For the additions, reclassifications and deletions to Y Pedwarau reported on Mapping Mountains since the May 2013 publication of the list by Europeaklist please consult the following Change Registers:

Myrddyn Phillips and Aled Williams (July 2017)