Tuesday, 3 March 2015

Mapping Mountains – Trimble Surveys – Moel Hebog


28.02.15  Ynys Galch (SH 567 393)

Ynys Galch (SH 567 393)
With a forecast of rain sweeping in from the west I met Aled in Porthmadog for another magical mystery tour of the Traeth Mawr islands.  But as the afternoon looked as if it was going to be very wet, I had been pre-warmed that the day’s tour was only going to be to some of the smaller islands.  However, they didn’t disappoint.

We parked opposite the Porthmadog War Memorial which constitutes a 16ft (4.9m) high Celtic cross and which was unveiled in 1922 and Grade II listed in 2005.

The Porthmadog War Memorial gives access to the summit of Ynys Galch
The Celtic cross of the War Memorial dominates a small rocky hillock which in its time would have been an inland island before the land of Traeth Mawr was reclaimed from the tidal swell of the sea with the building of the Cob.  The island’s name is Ynys Galch.
   
We crossed the busy road and walked up the 70 metre semi-circular walk way to the Memorial.  The view from beside it was negligible as the land was bathed in low grey murk, a foreteller of the high winds and heavy sweeping rain that would set in soon after we had completed our island adventure.

Aled led the way beyond the memorial, and as we left the sedate confines of tarmacked path and Celtic cross I looked ahead and all I could see were thickening Holly bushes and trees.  By keeping near to the crest of the hillock we quickly made progress, however we had to venture down on the northern side once, as the vegetation proved so thick that the only way to make progress on the crest of the island was to use a small sapling tree and swing around it to gain slightly clearer ground on its other side, as the tree was perched over a 15m drop we quickly backtracked.

Entering the labyrinth
Somewhere in the distance is the summit
Once through more Holly bushes we came to the high point which is in a small clearing measuring about one metre square and consisting of scrub ground overlooked by a gorse bush and trees.  I set the Trimble up and we waited, eventually it reached the required 0.1m accuracy before data can be logged, and once five minutes of data had been collected I packed it away and we re-traced our steps back through the undergrowth to the awaiting car.

I’d driven past this small island on countless journeys in the past but had never really paid its existence much thought.  If visiting the islands of Traeth Mawr is should be included, as should the next one we visited.

Gathering data at the summit of Ynys Galch


Survey Result:


Ynys Galch

Summit Height:  19.7m (converted to OSGM15)

Summit Grid Reference:  SH 56794 39309

Drop:  18.0m (non Double Sub-Twmpau status confirmed)

Dominance:  91.51%



For further details please consult the Trimble survey spreadsheet click {here}


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