Monday 24 July 2017

Mapping Mountains – Trimble Surveys – Y Berwyn


07.06.17  Comins (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 Comins

Moel y Gwelltyn from the Comins

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 Comins. 

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 the Comins.

Gathering data at the bwlch of the Comins

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, Trimble GeoXH 6000)  

Summit Grid Reference:  SJ 17476 28210 (Trimble GeoXH 6000)

Bwlch Height:  341.2m (LIDAR)

Bwlch Grid Reference:  SJ 17373 27995 (LIDAR)

Drop:  34.8m (Trimble GeoXH 6000 summit and LIDAR bwlch) (Sub-Trichant reclassified to Trichant)

Dominance:  9.26% (Trimble GeoXH 6000 summit and LIDAR bwlch)





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

Dominance:  37.62%






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


Dominance:  6.77%





Moel Lloran

Summit Height:  297.2m (converted to OSGM15)   

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%











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