Showing posts with label Moel Hafod yr Ŵyn. Show all posts
Showing posts with label Moel Hafod yr Ŵyn. Show all posts

Saturday, 24 January 2026

Mapping Mountains – Trimble Surveys – Arenig Fawr


13.12.25  Ffridd Trawsgoed (SH 837 328) and Moel Hafod yr Ŵyn (SH 841 322) 

Moel Hafod yr Ŵyn (SH 841 322)

There is bleak beauty in venturing on to rough, unremitting ground and especially so during the onset of winter where grey skies predominate and a brisk wind echoes across the land.

Today we visited two hills positioned just west of the southern most part of Llyn Tegid.  Both are relatively easy to access from the narrow road that winds its way across these hills toward Bronaber.  I hadn’t been on this road in many years and had not until today visited these two hills.

I met Mark and Aled in Y Bala, where we left two cars and then continued on the A494 road heading south-west beside the lake toward the minor road that in time would take us to our designated parking spot on a grass verge beside an old metal gate. 

Heading toward the forest track

The forecast gave south-westerly winds, so not chilled and relatively mild for the time of year.  I set off before Mark and Aled, but soon stopped and waited as the continuation of the way up the hill was indistinct with slender long grasses amongst bracken and stunted trees giving little indication of a path.  However, one did exist and once on it I followed my companions up to a forest track that shortly afterward bisected another track where a person was standing beside a gate.  As we approached we said hello; Andrew Graham was the landowner, his sister was standing a short distance further down the track.  We chatted for five minutes or so, he was concerned as the gate had been left open and wondered who had done it.  He’d come to the area in the 1960s having bought the land to turn it over to the conifer plantation that now surrounded us. 

Andrew Graham

As Andrew walked down the track to join his sister, we headed in the opposite direction looking for a convenient access point on to the upper hill, which now rose in front of us a mass of heather and roughness.  The going uphill from this point was steep and ponderous with no semblance of path.  It was hard work, but also a marvelous place to find oneself on a Saturday afternoon in December. 

The steep heathery slopes leading to the summit of Ffridd Trawsgoed

I arrived on top last out of the three and was immediately buffeted by the brisk wind.  Although I’d brought the Trimble I had little intention of using it unless the tops were covered in clag and then only as a hand-held GPS device.  However, I still placed it on the high point for the customary photograph. 

The summit of Ffridd Trawsgoed

To our south Moel Hafod yr Ŵyn looked a wild inviting hill, with a rather unpleasant bog between us and it.  Leaving the summit we stumbled our way down the steep pathless slope and back on to the relative comfort of the forest track.  However, the comfort didn’t last long as soon the bog would have to be tackled. 

Moel Hafod yr Ŵyn and its unsavoury looking bog

There’s a pleasing aspect to bogs.  Many are lush with copious amounts of undergrowth and this one was definitely one to savour.  Progress through it was never difficult and wearing vibram soled wellies certainly helped.  I followed Aled as he furrowed his way through, only stopping occasionally to regather my breath during which I looked at the slender threads of long grasses as they gently danced in the wind.  As I said; there is beauty in a bog. 

Mark tackling the bog

Mark soon joined us on the other side of the bog and as Aled headed up to gain height, Mark continued flanking the upper hill on the periphery of the bog before then heading up toward the summit cone.  Oh decisions decisions, what one to follow?  I opted for Aled and was soon being left behind as I made slow progress through the undergrowth.  By the time I spotted Mark he had gained height and was approaching the upper part of the hill, Aled was already nearing the summit.  I continued my slow plod up in to the realms of wind and views.

Aled heading toward the summit of Moel Hafod yr Ŵyn

The upper cone of Moel Hafod yr Ŵyn

The upper hill proved a delight with a small rock band to veer past.  Having reached the summit I did as I had done on top of Ffridd Trawsgoed and placed the Trimble on the high point for its customary photograph.  The view compensated for my tiredness, with the land to the west a wild and remote place of more tussocks, bog and rising hills, whilst to our south-east the descending slopes headed down to the gentler climes of the valley below. 

The summit of Moel Hafod yr Ŵyn

Leaving the high point I followed Aled down through mixed ground of heather and intermittent hidden rock.  Our route down led to a wall which had a barb wired fence perched menacingly on top of it.  This was not good news for the two elderly gentlemen in our walking party.  However, with the help of our younger colleague there was no mishap and soon we were standing on relatively safe ground on the other side. 

The last steep slope leading back on to the narrow road and the car parked beyond

From here it was only a short walk back to the car; with an initial steep slope leading on to the narrow road where we veered right and followed the thin width of tarmac a few hundred metres back to where we had started our walk from.

We were back in Y Bala at around 4.40pm and soon happily seated in the Plan yn Dre for an early evening festive meal, which proved an excellent way to end another good day on the hill. 

 

Survey Result: 

 

Ffridd Trawsgoed 

Summit Height:  423.9m (LIDAR)  

Summit Grid Reference:  SH 83755 32841 (LIDAR)

Bwlch Height:  384.2m (LIDAR)

Bwlch Grid Reference:  SH 83731 33086 (LIDAR) 

Drop:  39.7m (LIDAR)

Dominance:  9.36% (LIDAR)

 

 

Moel Hafod yr Ŵyn 

Summit Height:  398.2m (LIDAR) (significant height revision)  

Summit Grid Reference:  SH 84199 32238 (LIDAR)

Bwlch Height:  358.4m (LIDAR)

Bwlch Grid Reference:  SH 84033 32465 (LIDAR) 

Drop:  39.8m (LIDAR)

Dominance:  9.99% (LIDAR)

 

 

For further details please consult the Trimble Survey Spreadsheet 

Monday, 20 December 2021

Mapping Mountains – Significant Height Revisions – Y Trichant – The 300m Hills of Wales

 

Moel Hafod yr Ŵyn (SH 841 322) 

There has been a Significant Height Revision to a hill that is listed in the Y Trichant – The 300m Hills of Wales, with the summit height, bwlch height and their locations, the drop and status of the hill derived from LIDAR analysis initially conducted by Aled Williams and subsequently by Myrddyn Phillips. 

LIDAR image of Moel Hafod yr Ŵyn (SH 841 322)

The criteria for the list that this height revision applies to are:

Y Trichant – The 300m Hills of Wales – Welsh hills at or above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub list entitled the Sub-Trichant, with the criteria for this sub category being all Welsh hills at or above 300m and below 400m in height with 20m or more and below 30m of drop.  The list is authored by Myrddyn Phillips with the Introduction to the list and the renaming of it appearing on Mapping Mountains on the 13th May 2017, and the Introduction to the Mapping Mountains publication of the list appearing on the 1st January 2022.

Y Trichant - The 300m Hills of Wales by Myrddyn Phillips

The name the hill is listed by is Moel Hafod yr Ŵyn, and it is adjoined to the Arenig Fawr group of hills, which are situated in the central part of North Wales (Region A, Sub-Region A2), and it is positioned with a minor road to its south-west and east, and has the village of Llanuwchllyn towards the south-east. 

When the original 300m height band of Welsh P30 hills were published on Geoff Crowder’s v-g.me website, this hill was listed with a 389m summit height based on the spot height that appears on the Ordnance Survey 1:25,000 Explorer map, with the caveat that the uppermost 390m ring contour had been missed. 

Extract from the Ordnance Survey 1:25,000 Explorer map

After the accompanying sub list was standardised, and interpolated heights and drop values also included the details for this hill were re-evaluated and it was listed with 37m of drop, based on the 396m summit spot height that appears on the Harvey 1:40,000 Snowdonia South British Mountain Map and the 359m bwlch spot height that appeared on the Ordnance Survey Vector Map Local hosted on the Geograph website and which was entitled the Interactive Coverage Map. 

Extract from the Harvey 1:40,000 Snowdonia South British Mountain Map

However, it was not until LIDAR became available that the details for this hill could be accurately re-assessed.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height data that is now freely available for much of England and Wales. 

LIDAR summit image of Moel Hafod yr Ŵyn (SH 841 322)

LIDAR analysis gives the summit height of this hill as 398.2m and this comes within the parameters of the Significant Height Revisions used within this page heading, these parameters are:

The term Significant Height Revisions applies to any listed hill whose interpolated summit height and Ordnance Survey, Harvey or other interactive map summit spot height has a 2m or more discrepancy when compared to the survey result produced by the Trimble GeoXH 6000 or analysis of data produced via LIDAR.  Also included are hills whose summit map data is missing an uppermost ring contour when compared with the data produced by the Trimble or by LIDAR analysis.

Therefore, the new listed summit height of this hill is 398.2m and this was derived from LIDAR analysis, this is 9.2m higher than the originally listed summit height of 389m which appears as a spot height on the contemporary Ordnance Survey 1:25,000 Explorer map and 2.2m higher than the 396m summit spot height that appears on the Harvey 1:40,000 Snowdonia South British Mountain Map. 

 

The full details for the hill are: 

Group:  Arenig Fawr 

Name:  Moel Hafod yr Ŵyn 

OS 1:50,000 map:  124, 125

Summit Height (New Height):  398.2m (LIDAR)                                                           

Summit Grid Reference:  SH 84199 32238 (LIDAR) 

Bwlch Height:  358.4m (LIDAR) 

Bwlch Grid Reference:  SH 84033 32465 (LIDAR) 

Drop:  39.8m (LIDAR) 

 

Myrddyn Phillips (December 2021)