Sunday 10 February 2019

Mapping Mountains - Trimble Surveys - Carnedd Llywelyn


10.10.18  Bryn Eithin (SH 775 752), Cae Alen (SH 781 758) and Bwlch Mawr (SH 777 755)  

Bryn Eithin (SH 775 752)

To the south of Conwy and nestled between the B 5106 road and the Afon Gyffin to the west and the Afon Conwy to the east is an area of land with three summits of similar height, with the names of Iolyn Park and Gorse Hill now prominent for part of this land on contemporary Ordnance Survey maps.  The central and southerly summits are given a small uppermost 130m ring contour, whilst the northerly summit is given a 130m spot height on these maps.

The wooded surrounds of Bryn Eithin on the left, the grazing field of Cae Alen on the right and Bwlch Mawr in between

When these hills were first listed in the original Welsh P30 lists on Geoff Crowder’s v-g.me website, the southerly hill appeared as Iolyn Park and the northerly hill appeared as Iolyn Park North East top, whilst the central summit was not listed.

Local and historic place-name research has led me to believe that appropriate names for these three summits are:

Northerly summit:  Cae Alen (SH 78116 75814)

Central summit:  Bwlch Mawr (SH 77790 75561)

Southerly summit:  Bryn Eithin (SH 77584 75224)

Joining these three summits are two bylchau, with the bwlch between the northerly and central summits being of a height that only the higher of these two hills will qualify for P30 status, whilst the bwlch between the central and southerly summits being of a height that the southerly summit will qualify as a P30.

Prior to my visit I analysed these hills via LIDAR and today I wanted to survey each summit with the Trimble GeoXH 6000 and if opportunity arose to also make place-name enquiries.

LIDAR image of Cae Alen, Bwlch Mawr and Bryn Eithin

The southerly summit is now dominated by the Gorse Hill Caravan Park; which is a well maintained site perched on the hill side with expansive views over the Afon Conwy, the central summit forms a part of the Conwy Lodge Park; another site that has expansive views over the near river, whilst the northerly summit is still clinging on as a grazing field.

As I drove up the road to the Gorse Hill Caravan Park the sky shone blue and October warmth predominated.  I parked close to the entrance gate and started to gather all necessary equipment, just as I was about to set off Richard Davies pulled up in his van, Richard is local and an employee of the site, he was interested in what I planned to do and wanted to know my motives.  I explained where I hoped to visit and he kindly gave me directions and advised me where to park, he also confirmed the name of the southerly hill as Gorse Hill and the central one as Bwlch Mawr.  The latter information is substantiated by the Tithe map which gives the land where the central summit is situated as a part of Bwlch Mawr farm and having this name.

Having thanked Richard for his time I slowly plodded up the paved road between the manicured gardens and neatly kept chalets toward the high point of the site, from here a narrow path climbs steep grass to the summit of Bryn Eithin which is crowned with a water tank near its high point.  As I neared the top of the path a vehicle pulled up behind me and Rob Thomas-Evelyn called toward me.  Rob owns the Gorse Hill Caravan Park and he was concerned that someone was wandering about unannounced and asked me to visit the site office for health and safety protocols.

Thankfully Rob didn’t want me to back-track immediately and let me visit the summit first, once on the manicured summit area I was left to enjoy the expansive view toward the high eastern Carneddau.  The high point of this southerly summit is easy to identify and as the Trimble gathered its allotted ten minutes of data I walked the cliff edge that makes up the western flank of this hill.

Looking toward the high Carneddau from the summit of Bryn Eithin

Gathering data at the summit of Bryn Eithin

The drop plunged down accentuating the view which was enhanced by cloudless blue sky, it was a delight to be on such a summit and soak in the view.  Once data were gathered and stored I closed the equipment down, packed it away and sauntered down to the site office, where I greeted Rob, signed the visitor’s book and asked him about the hill and its name.  Rob confirmed the hill is known as Gorse Hill and unprompted referred to it as Bryn Eithin, which is the literal translation, he then explained that the central summit is known as Bwlch Mawr, although this is now a part of the Conwy Lodge Park.

The cliff top view from Bryn Eithin

The view from the summit of Bryn Eithin with Cae Alen the field on the right with cattle in and Bwlch Mawr is in the centre left of this photo with its summit obstructed by trees

Thanking Rob for his permission to visit the summit I headed back to my car and the short drive down on to the B 5106 road and then up toward the entrance to the Conwy Lodge Park, where I parked near to a public footpath which heads east through the site, and also diverts north toward the northerly summit.

The footpath led through an enclosed avenue with high fir trees to my left and scrub land to my right, and onwards through a kissing gate before heading across the paved access road in the site and up another enclosed path, this led to a high metal ladder stile which gave access to the northerly summit through an open gate.

The land where the northerly summit is situated is named as Cae Alen on the Tithe map with the farm of the same name situated to the north-west of the summit.  Once on the northerly summit I zeroed in to its high point, set the Trimble up and stood back as it gathered another data set.  As the Trimble beeped away collecting datum points I watched a herd of cows as they slowly munched their way a little nearer, thankfully they remained distant during the time I was on the summit.

Gathering data at the summit of Cae Alen

After packing the Trimble away I headed to the open gate and followed the footpath down to where it diverts south-east, here I entered the caravan site and started my wanderings proper.  Until now the two summits I had visited had been easy affairs to navigate, but I was now in amongst a maze of roads with many dead ends leading into small and secluded caravan sites.  I ended up in the White site and asked if anyone knew of a path heading up to what looked like horrendous gorse to where I imagined the central summit to be situated.  A woman said that there may be a path behind the shower block, I found what looked like this path but it only led to a small top enclosed by vegetation, therefore I checked the ten figure grid reference for the summit compared to my position.  I needed to head approximately 200 metres one way and 50 metres the other, so I back-tracked to the shower block and walked around a wide paved road looking to my right for a path that headed up toward a fence, beyond which I was sure this elusive central summit was placed.  At last I found a path that headed up to the fence, this could easily be circumvented and out I popped close to the central summit.

Within a few minutes the Trimble was set up gathering data, during the ten minute allotted data set I sat on a narrow path overlooking the continuation of the paved road I had been on and out toward Bryn Eithin.  It felt good to be here, seemingly without the proverbial care in the world, luxuriating myself in autumn warmth and having now gathered data from, and hopefully confirming, which of these three summits is the higher.

Gathering data at the summit of Bwlch Mawr with Bryn Eithin in the background

Cae Alen from the summit of Bwlch Mawr

It was only a short walk back through the site to my awaiting car once the Trimble had done its stuff and was packed away.  Leaving the Conwy Lodge Park I drove toward Conwy where I now wanted to visit Coed Bodlondeb (SH 779 781); a P30 that Mark Jackson had discovered in August 2015.



Survey Result:




Summit Height:  128.5m (converted to OSGM15) (confirmed as lower than Cae Alen [SH 78116 75814)

Summit Grid Reference:  SH 77584 75224

Bwlch Height:  95.5m (LIDAR)

Bwlch Grid Reference:  SH 77644 75447 (LIDAR)

Drop:  33.0m (Trimble summit and LIDAR bwlch)

Dominance:  25.67% (Trimble summit and LIDAR bwlch)






Summit Height:  129.1m (converted to OSGM15) (confirmed as higher than Bryn Eithin [SH 77584 75224] and Bwlch Mawr [SH 77790 75561])


Bwlch Height:  34.8m (LIDAR)

Bwlch Grid Reference:  SH 77629 74003 (LIDAR)

Drop:  94.3m (Trimble summit and LIDAR bwlch) (100m Twmpau reinstated) (prospective Subhump addition)

Dominance:  73.05% (Trimble summit and LIDAR bwlch)






Summit Height:  128.4m (converted to OSGM15) (confirmed as lower than Cae Alen [SH 78116 75814])

Summit Grid Reference:  SH 77790 75561

Bwlch Height:  110.9m (LIDAR)

Bwlch Grid Reference:  SH 78016 75713 (LIDAR)

Drop:  17.5m (Trimble summit and LIDAR bwlch) (100m Twmpau deletion) (prospective Subhump deletion)

Dominance:  13.64% (Trimble summit and LIDAR bwlch)




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