Mapping Mountains – Trimble Surveys – Arenig

27.09.14  Moel y Gydros (SH 914 453)  

Moel y Gydros (SH 914 543)

As I drove through Llanfyllin the drizzle started and beyond Llangynog the land had turned grey with low mist hugging all hills.  Remarkably Milltir Gerrig was free of mist but looking west was not very appetising as the murk was lower here than in the east and as I drove into Y Bala the drizzle was heavier.  It was a morning to have had an extra hour in bed or continue with assessing the Y Pellennig.

Instead I was heading for a rendezvous with Aled with a plan to visit two marginal hills, one a Pedwar (Y Gesail at SH 926 437) and the other a 400m Sub-Pedwar (Cerrig y Gordref at SH 930 428), these could be easily combined with one or two other hills and would make a good circuit with a descent to Llyn Maen Bras.

As I waited in a lay-by for Aled to arrive the mist thickened and the murk continued to drizzle, it really wasn’t very encouraging.  When Aled arrived we sat in his van for an hour and chatted.  During this time a tiny patch of lightening sky showed a slither of blue and as time continued this became larger, this at least was encouraging, but our planned hills were still grey and infested with murk.  Aled came up with an alternate plan involving a smaller and less committed walk visiting the summit of Moel y Gydros and if the weather improved we could then bag a couple of Pedwarau hills afterward.  So we headed off towards the top of the road that heads up Cwm Tirmynach.

We parked in a large passing place just on the southern side of the high point of the road and set off to the top of the road and then down a track to gain access to the upper part of Moel y Gydros.

As the weather was still a little iffy I put on my over trousers and Goretex coat and proceeded to feel as if I was walking in the tropics as a serious case of over-heating commenced.  The track continued downhill to its low point and then headed up toward the rounded summit ridge of Moel y Gydros, which is listed as a Submarilyn with 145m of drop.  This was something that I was unaware of  but which Aled quickly worked out by looking at the map contouring, its critical bwlch was beside the road a few hundred metres from where the car had been parked, so we could combine Trimbling the bwlch with a good small circuit of the hill.

When approaching Moel y Gydros from the west the hill portrays sides re-claimed from its moorland past with cows and sheep grazing green pasture, its recent past is evidenced by its neighbour; Moel Llechwedd-figyn whose rounded dome is more in nature with the hills in the area with reed grass and baiged colour portraying a wilder side to these hills.  However, an eastern approach to Moel y Gydros would give the walker a very different feel for the hill as from this direction its moorland appeal would be on full show as it is only its western side that is pasture.

The eastern side of the hill shows its wilder moorland profile

To the north stood Moel Eglwys (SH 905 478) a Pedwar Aled had not visited and if the weather kept improving it was a hill we hoped to visit after Moel y Gydros.  To our south-west cloud still clung to the higher Arennig but Craig yr Hafod and the rounded shape of Graig Ddu were now free of murk which heralded a continuing improvement in the weather.

Graig Ddu (SH 888 428) with the high Arenig still in cloud beyond

The summit of Moel y Gydros has a small cairn which I inspected for any higher hidden ground compared to the ground beside it, there was none, so the Trimble was positioned on the highest bit of land beside the cairn and sat happily gathering data for its allotted five minutes.  During this Aled sat and munched on a pasty and I pottered about taking photographs.

Gathering data beside the cairn at the summit of Moel y Gydros

The summit height came to 522.4m (converted to OSGM15), which is 1.4m higher than previously recorded

The time when the Trimble is gathering data does afford a few minutes to sit and relax and as the first survey of the day was in progress Aled chilled out and I happily scribbled down all relevant notes to include in the Trimble Survey Spreadsheet and admired the view.  This proved excellent as this hill is in a prominent position looking out on the wild heather moor of Carnedd y Filiast as well as neighbouring high cymoedd and lower heighted hills.

Aled taking a rest as the Trimble does its stuff

When the Trimble had done its stuff we headed down toward its critical bwlch which looked easy to place from above, but when we arrived its lower reaches on the valley to valley traverse was full of quagmired water, tussock and mud.  We assessed it from a number of directions with Aled heading up the adjacent road to get a better view of its placement.

If not for the steel bridge the Trimble may have ended up drowning in the quagmire of water and mud

The channel of water at its base seemed to have been dammed by the advent of the adjacent road, forming the small quagmire which did not have continuous run off down the northern valley.  The Trimble was eventually placed on a steel trailer side that had been placed over the water as a bridge and a 33cm offset measured to the water surface, a few minutes later once it had gathered its data I joined Aled at the car and we headed toward Moel Eglwys for a bag of a Pedwar.

Survey Result:

Moel y Gydros

Summit Height:  522.4m (converted to OSGM15)

Summit Grid Reference:  SH 91430 45386

Bwlch Height:  376.4m (converted to OSGM15)

Bwlch Grid Reference:  SH 90805 45033 

Drop:  145.9m (Submarilyn status confirmed)

Dominance:  27.94%



For further details please consult the Trimble Survey Spreadsheet