Monday 15 February 2021

Mapping Mountains – Trimble Surveys – Elenydd

 

22.10.20  Penpegws (SN 702 755) 

Penpegws (SN 702 755)

Penpegws is attractively positioned with the waters of Llyn Rhosrydd and Llyn Glandwgan below.  It has a solidary feel compared to many adjacent hills and this is emphasised by its broad south-western ridge which descends for almost three miles toward the small community of Abermagwr and the Afon Ystwyth below. 

This was the fourth of a planned seven hills during the day and prior to visiting all had been examined for numerical detail via LIDAR.  As of now LIDAR does not cover the whole of Wales, but for this hill both its summit and bwlch have coverage.  Therefore, with accurate bwlch data I wanted to visit its summit and also produce data taken by the Trimble GeoXH 6000. 

LIDAR image of Penpegws

The hill has options for an ascent route; I chose the bridleway heading toward the hill from the north-east, mainly as the starting point was beside the narrow lane that I used to approach the hill.  However, the map suggests an ascent from the south-west following the continuation of the same bridleway but in the opposite direction would be an attractive proposition. 

Having left my car squeezed beside a bank on a narrow tee-junction leaving just sufficient space for a vehicle to pass, I headed up the track leading to the farm of Rhos-rydd.  The forecast blue skies and sunshine had not yet materialised, and as I crested the top of the track before it heads down toward Llyn Rhosrydd a slightly chilled autumnal breeze blew scattering wind-blown leaves as it did so.  These crunched under my feet as I made progress on the track. 

The change of seasons is one of the most attractive aspects of hill walking and I think it fortunate to live in a country that gives opportunity to experiences this, and with those warm summer days when the landscape is parched and fields coloured dulled green now gone, autumn in all its finery is here with its cascade of colour that is all too often gone before truly appreciated and the westerly rain producing muddied tracks and chilled breezes necessitating extra layers of clothing.  It is a time to wrap up against the incoming elements and luxuriate oneself in that magical seasonal change. 

The summit of Penpegws rose above the near lake with the land highlighted by occasional breaks in the high cloud cover, with glimpses of the sun accentuating the colour which gave welcome addition to the scene. 

The track led to the farm and as I passed the yard I waved at the farmer who was in one of the outbuildings, he did likewise and we shouted our ‘hellos’, I signalled if it was all right for me to come over and he indicated for me to approach, but asked if I could keep my distance when nearing the building.  We chatted for a number of minutes; he was working with his son, I didn’t ask his name, but did for that of the hill; Penpegws he replied.  I asked if I could gain height on the hill to take some photos and he kindly told me where the gates were positioned to access the upper hill.  During our conversation I gave the few Welsh words that I know and these made him smile and turn to his son.  I’m thankful to the Welsh speaking fraternity of the farming community who always communicate with me in English, a language for many that was not the one they initially learnt.  Before leaving I thanked him in Welsh and waved my goodbyes. 

Llyn Rhosrydd

Banc Cwmnewydion (SN 718 749) rising above the shore of Llyn Glandwgan

I continued on the track which crosses the lake on its southern side and then swings around the south-eastern flank of the hill.  It was here where I accessed the upper hill through the gate the farmer had recommended.  The land now rose ahead and soon I arrived at the summit area of the hill. 

As I checked the co-ordinates given by the Trimble against those produced by LIDAR for the summit position, a flurry of breeze-blown raindrops scattered across the hill.  I turned my back to the breeze and hoped this did not herald heavier and consistent rain; thankfully it was no more than a small passing shower. 

The Trimble set-up position at the summit of Penpegws

The Trimble was soon set-up gathering data, during this I stood back and examined the map for an alternate descent route.  On my ascent I’d spotted two gates separated by a large field that would have given access to the summit, and this could easily be used for my descent.  Once the customary five minutes of data were gathered and stored, I closed the equipment down, took a few photos and packed it away. 

Gathering data at the summit of Penpegws

My descent route soon brought me back to the track crossing the southern side of Llyn Rhosrydd.  I hoped to see the farmer again as I passed the farm to wave my thanks, but he was no longer in the outbuilding, so I continued on my way following the track back to my car. 

Penpegws beyond Llyn Rosrydd from the bridleway and access track to the farm of Rhos-rydd

The walk had taken about 1 hour 15 minutes and was one of the most enjoyable during the day.  I think this was in part to meeting the farmer, but it was also that feeling of seasonal change brought on by the slight chilled breeze, the wisps of rain on the summit and flashes of colour across the land as the cloud base broke which heralded pleasant sunshine for the remainder of the day. 

 

Survey Result: 

 

Penpegws  

Summit Height:  317.3m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SN 70209 75565 (Trimble GeoXH 6000) 

Bwlch Height:  278.0m (LIDAR)

Bwlch Grid Reference:  SN 70578 76259 (LIDAR)

Drop:  39.3m (Trimble GeoXH 6000 summit and LIDAR bwlch)

Dominance:  12.39% (Trimble GeoXH 6000 summit and LIDAR bwlch)

 

 

For further details please consult the Trimble Survey Spreadsheet

 

 

 

 

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