Sunday, 24 January 2021

Mapping Mountains – Trimble Surveys – Elenydd

 

15.10.20  Banc (SN 568 757

Banc (SN 568 757)

Prior to visiting this hill I examined its details via LIDAR and the resulting data gives land to the south-east of the 192m map heighted trig pillar as the summit of the hill.  This land is given an uppermost 190m ring contour on contemporary Ordnance Survey maps, but no spot height.  With this information at hand Charles and I headed for the hill. 

LIDAR summit image of Banc

Banc is wonderfully positioned beside the coast, as indeed were our two previous hills that we had visited, and today, with a vivid blue sky above and the blue of the Irish Sea below, it was a sheer pleasure to be out on the hill. 

Banc is wonderfully positioned overlooking the coast

We approached from the south on a good track close to where another track heads up to the large mast which is prominent for many miles around and which is positioned just below the summit of this hill. 

The track leads toward the small ridge where the newly listed summit of this hill is situated.  Beyond is a green and grassed dip where the ruined remains of Esgair-hir are placed.  This old farm house was once substantial and Charles commented that its position in the dip was unusual and that it was probably built there to combat the westerlies blowing in from the sea. 

The old farm house of Esgair-hir

The ridge that has the new summit position on it is covered in gorse with a ridge fence close by and a vehicle track on the opposing side.  There are a few hummocks on the ridge and we spent a number of minutes assessing the lay of land and choosing our favoured spot for Trimble placement. 

Once the Trimble was set-up and gathering data we headed over to the listed Tump summit beside the trig pillar.  Beyond the old farm house we gained height toward an elevated field boundary and the trig pillar which is positioned on the opposite side. 

Gathering data at the summit of Banc

I quite like trig pillars, they give a welcome addition to many hills, but I have not been tempted like many others to start bagging them.  Charles on the other hand, wanted photos of its flush bracket and spider, I duly obliged.  Usually he would do this himself, but he had left his mobile phone in his van and therefore spent the whole day in my company without having access to the Internet and the use of his phone and camera, and if you know Charles, this is a rarity.  I quite liked this, as it left him without distraction except for the beauty of the hills and me as a companion. 

Charles at the trig pillar

Once photos of the trig had been taken we headed back to the Trimble which had been quietly beeping away gathering 840 individual data points.  After closing the equipment down, I took a few photos and re-joined Charles for our descent down our inward track. 

Three hills were now done, and if time and inclination permitted we had another six to visit, as well as what looked like an extremely large and uninviting bog for me to survey.  Our next hill; Banc Tan y Cwarel (SN 583 748) was only a short distance to our south-east and over the intervening A487 road.  The day was turning out to be a good one and it continued to be so! 

 

Survey Result:

 

Banc (significant name change)  

Summit Height:  194.2m (converted to OSGM15, Trimble GeoXH 6000) (significant height revision)

Summit Grid Reference:  SN 56817 75750 (Trimble GeoXH 6000) (summit relocation confirmed)

Bwlch Height:  130.2m (LIDAR)

Bwlch Grid Reference:  SN 57845 73062 (LIDAR)

Drop:  64.0m (Trimble GeoXH 6000 summit and LIDAR bwlch)

Dominance:  32.93% (Trimble GeoXH 6000 summit and LIDAR bwlch) (Lesser Dominant deletion)

 

 

For further details please consult the Trimble Survey Spreadsheet

 

 

 

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