Friday, 12 August 2022

Mapping Mountains – Trimble Surveys – Moel y Gamelin

 

20.06.22  Copa’r Frân (SJ 206 703), Moel y Crio (SJ 199 696) and Moel y Gaer (SJ 210 690) 

Copa'r Frân (SJ 206 703)

The land between Mynydd Helygain in the north and Moel y Gaer in the south is relatively open with occasional houses and farms dotting the landscape.  This area has been mined extensively, mainly for lead and limestone, and it still has a working quarry positioned just to the west of the three hills we planned on visiting today.

I was out with Mark Trengove, who had suggested this walk.  During the restrictions imposed due to Covid-19, Mark had used Moel y Gaer as his go to hill, racking up a multitude of ascents in the process.  This whole area is dotted with greened paths snaking between copious amounts of undergrowth and it proved an enjoyable experience visiting these hills with Mark acting as the local guide.

As an evening meal was planned with Mark and Louise we left our walk until mid-afternoon, by which stage the weather had warmed giving clear heat with a beautiful blue sky above casting vivid colour across the land.

These hills are easily visited as a myriad of narrow lanes criss-cross the area.  We parked close to the small community of Catch and then sauntered over grass heading toward the high masts positioned near the summit of our first hill of the day.

Nearing the top, Mark directed me toward the summit and I soon had the Trimble set-up gathering data.  It was good to be back out on a hill, with a few weeks spent away doing other stuff.  Once data were safely gathered and stored I packed the equipment away and we headed down to the few houses that nestle just below the high point of the hill.  Here we met Tina Cook, who was heading out to collect her daughter from school.  Tina explained that her family is local and she had lived here for 30 years.  We asked about the hill and whether it was known by a name, Tina told us its name is Copa’r Frân, which is also the name of her house.  Thanking her for her time, we left heading south-westward, bi-passing the large compound housing the masts and used a series of green paths toward our second hill of the day. 

Gathering data at the summit of Copa'r Frân

By now the heat of the afternoon was building, this was partly welcome but also rather debilitating.  I was glad of our route which was not too taxing, as the thought of attempting any prolonged walk in these warm conditions was not one to savour. 

Moel y Crio from Copa'r Frân

En route to our next hill we called at a farm and spent the next 15 minutes or so talking with the farmer, who confirmed the name of Moel y Crio for our next hill and proceeded to give us a variety of anecdotes about the local area.  Leaving the farmer, Moel y Crio loomed above with its northern aspect festooned in gorse.  However, my local guide knew where the path was and we were soon plodding our way up steepening slopes to the open ground at its summit.  During data collection we sat on grass below the equipment so as not to disturb satellite reception and munched on an assortment of pick-n-mix. 

The path through the gorse leading to the summit of Moel y Crio

Gathering data at the summit of Moel y Crio

The bwlch for Moel y Crio was positioned between us and our third and last hill of the day; Moel y Gaer, and once the Trimble was packed away I followed Mark down the steep path to the greened land below.  A track crosses the area of the connecting bwlch and we were soon debating where its critical point was positioned.  Once decided upon the Trimble was soon set up gathering its third data set of the day. 

Gathering data at the bwlch of Moel y Crio

Leaving the bwlch I followed Mark as we joined up with a series of narrow paths heading toward a pool, before joining one of the main paths leading up Moel y Gaer.  This hill was definitely the highlight of the day and is a worthy inclusion in the list of The Huws – 100 Great Welsh Hills under 2,000ft. 

Heading toward Moel y Gaer

The area of the summit is enclosed by an impressive ancient embankment which we followed around its southern side.  From this vantage point the view was extensive with late afternoon light enhancing our surrounds. 

On the southerly part of the ancient embankment encircling the summit of Moel y Gaer

A path leads from the embankment detouring toward the summit which consists of an ancient tumulus.  This point was surveyed with the Leica 530 in May 2009 resulting in confirmation that the tumulus is the high point.  However, in 1979 a covered reservoir was built on the summit area and its high point was found to be 0.63m higher than that of the tumulus, but as this is a relatively recent man-made construct it is discounted from the summit height of the hill.

The Trimble was soon positioned aligned with the summit on top of my rucksack with the measurement offset between its internal antenna and the ground at its base noted, and as individual datum points were collected I sat with Mark, below the equipment looking out toward the expanse of Liverpool in the distance. 

Gathering data at the summit of Moel y Gaer

It was now time to head down and a green path led us back to the awaiting car.  It had taken three hours to complete the walk; it proved a leisurely affair in excellent walking country. 

 

Survey Result: 

 

Copa’r Frân  (significant name change)

Summit Height:  286.1m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SJ 20624 70354 (Trimble GeoXH 6000)

Bwlch Height:  265.7m (converted to OSGM15, Leica GS15)

Bwlch Grid Reference:  SJ 20803 70065 (Leica GS15)

Drop:  20.4m (Trimble GeoXH 6000 summit and Leica GS15 bwlch) (200m Sub-Twmpau addition)

Dominance:  7.12% (Trimble GeoXH 6000 summit and Leica GS15 bwlch)

 

 

Moel y Crio

Summit Height:  297.5m (converted to OSGM15) (significant height revision)

Summit Grid Reference:  SJ 19988 69614 (summit relocation)

Bwlch Height:  276.8m (converted to OSGM15)

Bwlch Grid Reference:  SJ 20406 69385

Drop:  20.7m (200m Sub-Twmpau addition) (Welsh Sub-P15 reclassified to Welsh P15)

Dominance:  6.96%

 

 

Moel y Gaer

Summit Height:  303.7m (converted to OSGM15, Leica 530) 303.8m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SJ 21065 69078 (Leica 530) SJ 21065 69078 (Trimble GeoXH 6000)

Bwlch Height:  176.2m (LIDAR)

Bwlch Grid Reference:  SJ 11953 75033 & SJ 11953 75031 & SJ 11954 75028 & SJ 11953 75027 (LIDAR)

Drop:  127.4m (Leica 530 summit and LIDAR bwlch) 127.6m (Trimble GeoXH 6000 summit and LIDAR bwlch)

Dominance:  41.97% (Leica 530 summit and LIDAR bwlch) 41.99% (Trimble GeoXH 6000 summit and LIDAR bwlch) 

 

 

For further details please consult the Trimble Survey Spreadsheet

 

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