Saturday, 27 November 2021

Mapping Mountains – Trimble Surveys – Moel y Gamelin

 

20.09.21  Windy Hill (SN 307 548) 

LIDAR image of Windy Hill (SJ 307 548)

The summit of this hill seemed relatively easy to reach, as examining the local roads with the aid of a Google Car showed a convenient parking place just to the north of the summit next to a gravel track and paved drive, with the latter leading to a house.  Above the paved drive was a field and the summit was either in the corner of it or across a boundary wall in a wood that forms a part of a disused quarry. 

I decided against a direct route up the field via the paved drive as it looked as if the land formed a part of the house’s garden.  Instead I opted for the gravel track.  This led past a number of houses with no direct access to the east which would take me up toward the summit.  However, even with direct access the continuing route from this direction did not look welcoming with an overgrown wood and no sign of a path, so I continued until reaching the end of the gravel track at a house named Rock Cottage. 

Once next to the cottage the gravel track swung leftward and upward, I followed it.  I now entered an overgrown small field above and also beside, the cottage.  I hoped this would give access to the field beyond a large unsavoury and overgrown hedge that barred me from where I wanted to go.  It didn’t, so I backtracked and found an alternative path that took me around and up the southerly flank of the hill.  However, although this path was good it was taking me away from the summit so I clambered over a collapsed gate and tried my utmost to avoid a patch of nettles.  Usually collapsed gates are relatively easy to get over, this had other obstacles involved and landing on the other side gave me hope that I would get to the summit in one piece.  I was now in the field leading toward the top of the hill, the view to my north-east opened up looking out across the flatlands leading in to England. 

The path leading toward the collapsed gate

Prior to visiting this hill I had LIDARed its summit and noted the ten figure grid reference to be a few metres from that given on the Hill Bagging website.  I hoped the LIDAR co-ordinates to be correct as it looked as if this was in a field beside the boundary next to the wood and disused quarry, whilst the summit position given on the Hill Bagging website gives the high point a few metres over a fence amongst trees. 

The field leading toward the summit

When I reached the top of the field I activated the Trimble and used it as a hand-help device and zeroed in to the co-ordinates I had noted from the Hill Bagging website, it pointed toward a fence made of cut and fashioned branches.  This was higher than a normal fence and for my no longer young and lithe frame proved another cumbersome obstacle to overcome.  Eventually I made it in to the wood on the opposite side and stood on the mound that Hill Bagging gives as the summit.  This position certainly looked the high point, but the LIDAR position was farther north toward a wall and boundary corner, I headed that way to have a look, but soon came back satisfied that the mound was higher. 

The fence leading in to the wood with the summit just beyond

I examined the ground and found a small embedded rock which I judged to be the high point and therefore I soon had the Trimble set up on top of my rucksack, and with the measurement offset noted between its internal antenna and the ground at its base I set it to ebb down to its 0.1m accuracy level before data should be logged.  This took about 20 minutes to achieve, but I was happy enough in the wood, not doing much, just standing, relaxing and recovering from cumbersome fence crossings.  Once the 0.1m accuracy level was attained I pressed ‘Log’ and stood back and below the equipment so as not to disturb satellite reception. 

Gathering data at the summit of Windy Hill

During data collection nothing else stirred, I ate a boiled egg and waited whilst looking down in to the bottom of the discussed quarry.  Prior to the quarry I suspect the natural summit of this hill was higher than where the Trimble was now placed, with LIDAR contouring suggesting the summit had been quarried away. 

The onward route from the summit and down the field

After five minutes of data were gathered and stored I closed the equipment down and headed to the boundary wall and the path on its opposing side.  This followed the wall down, but I suspected it ended in someone’s back garden or just petered out, so I followed another path adjacent to the fence that formed the boundary with the field where I had been earlier, this thankfully led on to the open field above my car.  I wandered down it and was soon overlooking the house at the end of the paved drive.  Just as I headed toward steps leading down to the paved section a man appeared and I waved and apologised for suddenly appearing in his back garden, he smiled and we chatted for about ten minutes or so.  He told me about the sections of undergrowth he had cut to make the path I had just been on.  He proved very pleasant to meet and when I asked him about the name of the hill, he replied that it is known as Windy Hill. 

 

Survey Result: 

 

Windy Hill

Summit Height:  174.0m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SJ 30743 54849 (Trimble GeoXH 6000)

Bwlch Height:  131m (spot height)

Bwlch Grid Reference:  SJ 30729 53674 (spot height)

Drop:  43m (Trimble GeoXH 6000 summit and spot height bwlch)

Dominance:  24.73% (Trimble GeoXH 6000 summit and spot height bwlch)

 

 

For further details please consult the Trimble Survey Spreadsheet

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