Wednesday 17 April 2019

Mapping Mountains – Trimble Surveys – Mynydd Twr


28.10.18  Mynydd Bach (SH 389 767)  

Visiting the summit of this hill seemed an easy affair, as logged ascents on the Hill Bagging website mainly used the access track to the north-west that leads to the two high masts and covered reservoir positioned on the summit area of the hill.  As well as giving an easy and convenient ascent it was also a short one, as it only involved a couple of hundred metres to the top.

However, as I drove up the narrow lane and arrived at the start of the track I found a high metal fence barring access, where the fence ended each side was well protected with brambles and unforgiving amounts of unsavoury undergrowth.  I parked my car for a good inspection and did consider trying to climb the locked fence, but smiled at the thought as I knew I would not be able to do this, even if wanting so, which by the way, I didn’t.

Having walked a short distance on the lane either side of the metalled fence I realised I would not be gaining access to the hill from this direction and therefore drove the short distance back down the lane to the small community of Gwalchmai and then drove north up another narrow lane which brought me to the east of the hill.  I found parking beside a gate that gave access to another track leading toward the hill, I decided to investigate.

The track led through a paddock where three horses were standing in the morning sun, one showed particular interest in me as I quietly headed up toward a mass of gorse, bracken and brambles with the summit just beyond.  This form of undergrowth is prevalent on many of the lower hills on Ynys Môn, and all that I have encountered can either be bi-passed or bashed through, but summer ascents wearing shorts is definitely not recommended!

The high ground of the paddock led me to two gates which gave access to an old stone wall and the mass of unsavoury undergrowth on the other side, but as the masts and the summit of the hill were now within reach there was only one thing for it, and within a minute or so I was over the remnants of the wall and heading through the gorse, bracken and brambles.  This conveniently led directly to the natural high point of the hill which LIDAR analysis gives as ground close to a small fenced compound where one of the masts is situated.

Within a few minutes I’d assessed the ground, stomped on a few brambles and set the Trimble up to gather data.  As the set-up position was beside the compound amongst lush vegetation I decided to gather a ten minute data set.

The Trimble set-up position at the summit of Mynydd Bach

As the Trimble quietly beeped away gathering its allotted data I roamed around the summit area, climbing the outer steps to the fenced reservoir and looking back on the Trimble which was hard to see through the mass of gorse and brambles.

Once data were gathered and stored I closed the equipment down, packed it away and tried to remember my inward route back through the unsavoury stuff.  Eventually I clambered over the old wall back on to greened land where the friendly horse wandered my way and followed me as I headed back through the paddock to my car.  All that remained was to make place-name enquiries as the hill remains unnamed on the map.

Gathering data at the summit of Mynydd Bach

The first house I called at was next to where my car was parked; the occupant was obviously in bed when I knocked on the door as when he opened it he was bare chested and still doing his trousers up, we talked for a number of minutes and he kindly directed me down the lane to the first of two small houses where he said the elderly woman would probably be able to help.

I walked down the lane toward the house with the rough and rocky slopes of the hill on my left, as I did so a man appeared and walked toward a plot of land where his daughter was planning to live.  Gwyn Thomas lived at one of the houses I’d passed on the lane; the hill was on the other side of the road to where his daughter was planning to live and was at the back of Gwyn’s house.  I introduced myself and explained my interest in hill names and asked if he knew a name for the hill; he replied immediately and told me its name is Mynydd Bach.

Gwyn Thomas with Mynydd Bach in the background

We talked for a number of minutes before I headed back up the lane after thanking Gwyn for his time.  Mynydd Bach is a proper little mountain, rough and rocky and with extensive views from its summit.  I was glad to have visited, even though the undergrowth had proven problematic, another hill bagged and just as important; another name documented.    



Survey Result:




Summit Height:  96.5m (converted to OSGM15, Trimble GeoXH 6000) (significant height revision)

Summit Grid Reference:  SH 38964 76773 (Trimble GeoXH 6000)

Bwlch Height: c 64m (interpolation)

Bwlch Grid Reference:  SH 40259 77918 (interpolation)

Drop:  c 32m (Trimble GeoXH 6000 summit and interpolated bwlch)

Dominance:  33.66% (Trimble GeoXH 6000 summit and interpolated bwlch)














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