Mapping Mountains – Trimble Surveys – Mynydd Pencarreg

31.07.18  Mynydd Llanybydder (SN 535 395)

Mynydd Llanybydder (SN 535 395)

I headed toward Mynydd Llanybydder after visiting Mynydd Pencarreg, these two hills are bisected by the upper reaches of the stream valleys of the Afon Duar and Afon Melinddwr, with the B4337 following the course of each between the small communities of Llansawel in the south-east and Llanybydder in the north-west.

Persistent rain fell as I drove up the minor road that covers the forested north-easterly slopes of this hill, thankfully the rain was not heavy and with a brisk breeze I hoped this would soon clear, although I wondered if I would have to wait an hour for it to do so, or venture out and get wet, miraculously when I arrived at the top of the road and parked adjacent to a cattle grid close to the access track that leads to one of three high transmitting masts that are positioned close to the summit of this hill, blue skies had appeared and the wet murk although still relatively close was being swept away.

Within a couple of minutes of setting off walking I had positioned the Trimble on the highest part of the ancient tumulus that also incorporates this hill’s triangulation pillar and stood back as five minutes of data were gathered and stored.

Gathering data at the old summit of Mynydd Llanybydder

During data gathering I looked out to the near forestry as I wanted to investigate where LIDAR gives the high point of this hill to be positioned, according to LIDAR this is not at the tumulus, and is immersed amongst the conifer plantation.

The Trimble set-up position at the old summit of Mynydd Llanybydder

Once five minutes of data were gathered I packed the Trimble away and headed toward the trees where a semblance of a track headed eastward, with the remains of felled ground to the south and forestry to the north. 

To follow this rough track I had one barbed wire fence to clamber over, as I did so, one prong of wire stabbed me and I emerged on the other side of the fence with blood spurting out of the wound.  I looked at my knee as blood freely flowed down my leg to my sock and boot, I’d grazed and scratched myself on wired fences a multitude of times over the years but spurting blood was somewhat of a novel experience.  I wiped the wound with a clump of grass to see where the cut was positioned, more blood quickly gushed out, deciding I was not going to die I pressed on in to the forestry.

Barb wired fences aren't my favoutite

I’d come prepared with a ten figure grid reference where LIDAR gives the high point of this hill to be situated and proceeded to use the Trimble as a hand-held device to get me to this point, thankfully this was not too far in to the trees.

It was hard to judge if this ground is higher than that beside the trig pillar on top of the ancient tumulus as there is no direct view between each due to the trees, and even if there was a direct view, it would still be difficult to judge which was higher purely by eye as the tumulus rises relatively steeply from the ground at its base whilst the ground heading in to the trees only rises gently over a much greater distance.

Looking back at the ancient tumulus and trig pillar from the periphery of the trees

Somewhere in the trees is the LIDAR summit of Mynydd Llanybydder

Once at the position LIDAR gives as the summit I visited a number of what could be construed as high points and exited the trees via a bit of branch bashing.  It felt good to be out of their darkened depths.

The Trimble marks the spot - the LIDAR summit of Mynydd Llanybydder

By now the blood from my knee wound had stopped spurting and on my way to the car I visited two engineers working at one of the masts, they kindly gave me wet wipes, plasters and a bandage, once the wound was cleaned I put three small plasters on it, thanked them for their help and walked the short distance back to my car, next stop the hills above Caerfyrddin (Carmarthen).

All cleaned up and ready to go

Survey Result:

Mynydd Llanybydder

Summit Height:  408.7m (LIDAR)

Summit Grid Reference:  SN 53589 39599 (LIDAR) (summit relocation confirmed)

Bwlch Height:  c 287m (interpolation)

Bwlch Grid Reference:  SN 56098 40547 (interpolation)

Drop:  c 122m (LIDAR summit and interpolated bwlch)

Dominance:  29.78% (LIDAR summit and interpolated bwlch)

For further details please consult the Trimble Survey Spreadsheet