Mapping Mountains – Trimble Surveys – Mynydd Sylen

31.07.18  Llain Fawr (SN 428 202)

Llain Fawr (SN 428 202)

Llain Fawr is only a small heighted hill, but it is easily picked out from adjacent hills to its south which I had visited earlier in the day.  It sits above the small community of Llangunnor, its Church and Chuch Farm and the car park for the Church gives easy access to its summit.

Prior to visiting I’d analysed this hill’s summit and bwlch via LIDAR and come prepared with the ten figure grid reference for its summit.

LIDAR image of the summit of Llain Fawr

LIDAR image of the bwlch of Llain Fawr

It was only a few minutes’ walk up the remainder of the car park to a gate which gives access to the top field, a vehicle track led across the south-eastern flank of the field and I followed this until near the boundary hedge close to the summit of the hill.

Once the Trimble was positioned atop my rucksack to give it elevation above its immediate surrounds and the 0.1m accuracy level attained before data should be logged, I pressed ‘Log’ and stood back looking south toward the hills I had visited earlier in the day.

The sound of the beep, beep, beep of the equipment as each datum point is collected quietly blew in the afternoon’s breeze as I stood looking out at a land that I had not previously visited.  This part of P30 bagging when new land is visited signifies a form of investigation and for me this brings a sense of fulfilment.

Gathering data at the summit of Llain Fawr

The Trimble set-up position at the summit of Llain Fawr

Once the allotted data were gathered and stored I packed the equipment away and headed back to my car to change out of my walking gear and drive the short distance to Caerfyrddin (Carmarthen), where I was staying the night with a friend who was house sitting for one of her friends.  Tomorrow we had planned a six hill bagging road trip to enjoy.

Survey Result:  

Llain Fawr (significant name change)

Summit Height:  80.8m (converted to OSGM15)

Summit Grid Reference:  SN 42855 20265

Bwlch Height:  23.0m (LIDAR)

Bwlch Grid Reference:  SN 42905 19831 (LIDAR)

Drop:  57.8m (Trimble summit and LIDAR bwlch)

Dominance:  71.49% (Trimble summit and LIDAR bwlch)

For further details please consult the Trimble Survey Spreadsheet