Thursday 8 November 2018

Mapping Mountains – Trimble Surveys – Brandy Hill


01.08.18  Castell Meherin (SN 146 117)

The summit of Castell Meherin (SN 146 117)

Castell Meherin was the sixth and last hill that Suzanne and I visited during the day, we could have pressed on and visited and surveyed a seventh, but with Suzanne’s son waiting for us in Caerfyrddin (Carmarthen) we decided to call a halt to our little bagging bonanza after visiting this hill’s summit.

The hill is positioned with the B4314 to its north and has a minor road to its south, and it was from the south that we approached.  Castell Meherin has a 205m map height, which matches that of Brandy Hill (SN 213 133) and these two summits were once classified as twin Marilyns, but the accolade as the accepted higher hill has gone to that of Brandy Hill in recent years, and as one had already been Trimbled earlier in the day I was looking forward to the result of this survey which I suspected would confirm the present classification of each hill (little did I know that they would come out exactly the same; 205.077m!)

I parked on the grass verge, just sufficiently off of the minor road not to course obstruction and we headed toward an access gate that led up a field, by now the afternoon’s blue sky had been replaced with monochrome cloud cover that heralded a weather front predicted to bring heavy and consistent overnight drizzle.

We aimed for a gap in the boundary hedge toward the top right of the second field we entered, according to the map this is where the ancient earthworks are situated that give their name to this hill, it is also where a trig pillar sits atop one of the embankments, however when we arrived all we saw was bracken, and masses of it.

As we approached the base of the mass of fern I just caught a quick glimpse of the top of the trig pillar, it seemed as if it was floating on the bed of bracken, beached and almost unobtainable.  I entered the jungle of bracken but quickly gave up and reversed what little distance I had made, perhaps entering from the far northerly corner would be easier?

We looked for an access path as we walked around the base of the embankment, none was found, and so I dived in from the far north-eastern corner and made head-way through bracken that almost swamped me and which was chest high, with sections over my head, this was proving fun!

Being swamped by bracken

Progress was being made but it felt more like swimming than hill walking, and once in the ditch it was only a short steep pull up to the embankment where the trig pillar and the summit of the hill is situated, Suzanne quickly joined me.

The high point of Castell Meherin is close to the base of the trig pillar and approximately the same height as its base which is placed on a lump of concrete, and as this ground was overgrown with bracken and bramble I placed the Trimble on top of the trig pillar and we sat under it as it beeped away gathering its allotted data.

Gathering data at the summit of Castell Meherin

Once five minutes of data were gathered I closed the equipment down, packed it away and we reversed our inward route back to the field below.  It had been a fun day out with Suzanne visiting and Trimbling six hills, with four of them Marilyns.  Next stop Caerfyrddin (Carmarthen) where an excellent Indian meal awaited.



Survey Result:


Castell Meherin (significant name change)

Summit Height:  205.1m (converted to OSGM15) (Dominant re-twinned with Brandy Hill [SN 21352 13359] with the Trimble result giving the height of both summits exactly the same; 205.077m)

Summit Grid Reference:  SN 14646 11773

Bwlch Height:  162.2m (LIDAR)

Bwlch Grid Reference:  SN 18517 12805 (LIDAR)

Drop:  42.8m (Trimble summit and LIDAR bwlch) (Brandy Hill is being listed as the prioritised summit for drop purposes)

Dominance:  20.89% (Brandy Hill is being listed as the prioritised summit for dominance purposes)









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