Mapping Mountains – Trimble Surveys – Arenig

27.09.14  Pt. 442.8m (SH 932 454) and Moel Gwern Nannau (SH 938 457)  

Moel Gwern Nannua (SH 938 457)

These two hills; one a 400m Sub-Pedwar and the other a Pedwar combine as the eastern arm of Moel y Gydros as the high moor of the Arennig heads downward toward the A5 road at Cerrigydrudion.  From afar these two hills are easily distinguishable as one of Wales’ first small wind farm’s is positioned on the area of the connecting bwlch.

Previously Aled and I had visited Moel y Gydros (SH 914 453) and Moel Eglwys (SH 905 479), by the time we had descended from the latter the afternoon light was turning to early evening glow.  Across the expanse of the Afon Ceirw lay Moel Gwern Nannau and its 442m map heighted Sub, each accessible from a high road that runs near to the bwlch between the two.  We didn’t need much encouragement and headed on the narrow lanes to our last objective of the day.

We parked at SH 933 455 where the entrance track to one of the turbines gave sufficient space for one or two cars.  Our first objective was the 400m Sub-Pedwar which I hadn’t visited before.  Once at the top we realised that two points would have to be surveyed, each in turn had the Trimble placed on their highest point and each had five minutes of data gathered.

Gathering data from the high point of the 400m Sub-Pedwar

We were soon walking down the narrow lane toward the area of the bwlch which is accessed on a footpath and track that leads to another wind turbine.  The bwlch area was uneven in its depths as grazing cows had left many a hoof print embedded in the mud of bog and reed grass.  Although the bwlch was expansive it was not difficult to judge where the critical bwlch for the current Sub-Pedwar is approximately situated.  After five minutes of data were collected we headed up to the summit of Moel Gwern Nannau.

Mmmm, yummy, another bog - at the bwlch between the hills

Across the expanse of pasture and moor the high Arennig rose monolithic in shape, dominating the horizon, a grey silhouette of mountain looking down on green, quiet pasture.  It seemed almost unobtainabley huge, accentuated by late afternoon light, rising out of gentle lands to a block of mountain grey.

Arenig Fawr monolithic in shape rising above green pasture

To our south lay Foel Goch (SH 953 422) which resembled a patchwork of field and colour, the tranquil greens edged into the moorland browns and all culminating in the gentle rising dome of Foel Goch.

Patchwork fields lead up to the summit of Foel Goch

As the spot for Trimble placement was chosen on the summit of Moel Gwern Nannau I stood a safe distance down slope to let the equipment gather data without obstructing its view of satellites, during this Aled went to investigate a subsidiary summit which is given a small c 450m ring contour, we both thought this lower when compared to where the Trimble was placed on the 452m map heighted summit.

Looking out toward the high Arenig from Moel Gwern Nannau

Gathering data from the summit of Moel Gwern Nannau

As the Trimble recorded the last of its 300 one second interval points, Aled re-joined me and said that the view from the subsidiary summit confirmed what we thought, that this summit is higher.

Pt. 443m - the Sub-Pedwar from the upper slopes of Moel Gwern Nannau

In all four data points had been surveyed on these two hills, and 70 minutes after leaving the car we were walking back up the narrow lane happy in the knowledge that we had salvaged a day’s hill bagging from one that at midday seemed full of murk and drizzle.   

 

Smooth and velvet land

Survey Result:

Pt. 442.8m

Summit Height:  442.8m (converted to OSGM15)

Summit Grid Reference:  SH 93211 45431

Bwlch Height:  415.7m (converted to OSGM15)

Bwlch Grid Reference:  SH 93644 45646

Drop:  27.0m (400m Sub-Pedwar status confirmed)

Dominance:  8.04%

Moel Gwern Nannau

Summit Height:  452.0m (converted to OSGM15)

Summit Grid Reference:  SH 93801 45746

Drop:  47m

Dominance:  10.40%




For further details please consult the Trimble Survey Spreadsheet