Showing posts with label Colfa Hill. Show all posts
Showing posts with label Colfa Hill. Show all posts

Monday, 9 August 2021

Mapping Mountains – Trimble Surveys – Fforest Glud


12.060.21  Colfa Hill (SO 194 553, previously Trimbled), Cefn Hir (SO 205 550), Caety Traylow (SO 197 561) and Cnwch Bank (SO 186 554) 

Cefn Hir (SO 205 550)

With the weather set fine, albeit warming up in the afternoon, I headed back to the Radnorshire hills in the company of Aled.  Today we wanted to visit the hills around and including Colfa Hill.  This small grouping of hills form a block of high land between the main Fforest Glud massif to the north and Gwaun Ceste and Glascwm to the west and south-west respectively. 

We had a number of surveying objectives that unusually didn’t include the highest hill; Colfa Hill, which had been surveyed with the Leica GS15 and Trimble GeoXH 6000 in October 2015, this was also the last survey that John, Graham and I did together. 

Having asked permission to park on a small strip of tarmac adjacent to the narrow lane and a house close to Colfa Farm, we were walking by 9.10am following a track up to a path through the periphery of a near wood and then out on to fields and eventually the open hill. 

Ahead lay the continuation of the track heading off in to the distance with infant fern sprouting their new and fresh greens and darkened heather all intimating that in these parts if a path or track is found it is best to follow it.  As height was gained the view soon opened up and in the distance the distinctive profile of the Malvern Hills was easily picked out. 

Always a welcome sight to see when on the hill

We soon stopped to watch three moorland ponies who nonchalantly looked our way, two white and one brown; they stood close to a sea of fern on a small patch of cropped grass with the near hillside descending to the valley below and distant hills forming a backdrop.  It was a lovely scene to behold early in the morning, where except for a welcoming cooling breeze and the ever present song of the Skylark nothing seemingly stirred. 

One of the moorland ponies on our way to Colfa Hill

Leaving the ponies we continued on the track toward a small pool.  We had a number of options how to visit the hills on our circuit with Colfa Hill; our high point of the day, either being the first or third hill to visit.  From beside the small pool the triangulation pillar on top of Colfa Hill looked ever so close and as the track headed up toward it we decided to visit this hill first. 

The small pool on the way to Colfa Hill

I hadn’t visited Colfa Hill since surveying it with John and Graham in October 2015, prior to this I had visited the hill on three occasions and therefore this was my fifth visit.  A surprising total when I checked my tick-lists.  As the summit had already been surveyed with the Leica and Trimble I did not gather further data and stood enjoying the view after taking a few photos of Aled beside the trig pillar. 

Aled at the summit of Colfa Hill

Leaving the summit of Colfa Hill we soon found an overgrown track heading in the direction of our next hill; Cefn Hir, which lay ahead of us as a patchwork of browns and greens with patches of cut heather giving a hope of relatively easy underfoot conditions leading to its summit. 

Heading toward Cefn Hir

The track wound its way around the upper part of a steep sided dingle that glowed back as sunlight and shade worked magical tricks upon the land.  From here we set off over patches of heather toward the connecting bwlch which was the first point to survey.  Two positions were surveyed for the critical point, both on the valley to valley traverse. 

Nearing the bwlch of Cefn Hir with Mynyddoedd Duon in the background

After packing the equipment away we re-joined the track and were soon standing on the summit of Cefn Hir.  We spent a few minutes assessing the lay of land for the high point and having decided the summit lay close to the edge of a patch of cropped heather the Trimble was soon set up gathering its allotted data.  During data collection Aled sat looking out to the wilds of deepest, darkest England which spread out before him, whilst I stood scribbling all necessary detail in my surveying notebook. 

The Trimble set-up position at the summit of Cefn Hir

When the sun is out and a cooling breeze skims across the tops, the Radnorshire hills are always a delight to visit.  They are quiet places, with few hill walkers, but they give a tranquil habitat where peace of mind is easily found with contentment of place and view that much other upland in Wales cannot match. 

Looking beyond the Mawn Pools to our route from Cefn Hir

Our route now headed north-westward toward the summit of Caety Traylow with another more than welcome track leading us toward its high point.  This track stretched out across the moor, a beacon not to waver from.  We stopped beside the Mawn Pools which nowadays is mainly a flat bedded land of cotton grass and no doubt bog, but a pool still exists, although probably much smaller than in years gone by.  Following the land of the Mawn Pools west would lead to the bwlch of Caety Traylow, but first its summit was to be visited and surveyed. 

LIDAR summit image of Caety Traylow

We left the track to head off over small patches of heather and bilberry to the summit of Caety Traylow, this was the only point on the day’s walk that was covered by LIDAR.  Having arrived at the summit and assessing the lay of land we were of the opinion that slightly higher ground was to be found about three metres from where LIDAR gives the position of the summit, and this is where the Trimble was set up.  During data collection I sat with Aled and ate an egg sandwich; a much needed bit of replenishment as the heat was slowly but surely taking its toll. 

Gathering data at the summit of Caety Traylow

The next point on the day’s surveying agenda was the bwlch of Caety Traylow which looked as if it was placed in a bog.  This is the continuation of the land heading up from the Mawn Pools which we had passed on our way to the hill’s summit.  On our way to the bwlch a lone walker was spotted heading up a track between the summits of Caety Traylow and Colfa Hill.  As we approached the area of the bwlch the same walker was heading back down, and except for this sighting we just had Skylarks as company, these little birds gave a background of ever present song; a joy to here at this time of year. 

I used the ten figure grid reference from the spot height that appeared on the Ordnance Survey Vector Map Local that was hosted on the Geograph website to zero in to the position of the bwlch.  However, land hereabouts comprised heather, reed grass, tussocks, a number of small grassed channels and small stagnant pools, therefore its critical position may be best decided upon when LIDAR is available for this area.  As the Trimble quietly beeped away gathering data I sat on a tussock savouring the position I was now in, if not for this esoteric pastime of surveying hills I would never have visited this place.  Probably for good reason, as I suspect during much of the year this bwlch is a quagmire of bog, thankfully today it was relatively dry and a delight to visit. 

Gathering data at the bwlch of Caety Traylow

Just one hill remained to survey; Cnwch Bank, which forms the descending westerly ridge of Colfa Hill.  Using this ridge as our descent gave an alternate route down as otherwise we would have doubled back on our inward route.  It also gave an opportunity to add accurate heights for this low prominence hill for both its summit and bwlch. 

We took two data sets from the bwch of Cnwch Bank on the hill to hill traverse and a further two data sets for its high point, with the first of the latter sets our preferred position for this hill’s summit.  As the Trimble gathered the last of these data sets I knew the heat had battered me.  Unfortunately my body does not react well to heat, it never has, however enjoyable a warm summer day can be and especially so when on the hill.  Over many years I have accustomed myself to be wary of undue exercise when summer temperatures increase, therefore nowadays I try and pick routes with less mileage than perhaps a few years ago; just enough to enjoy, but not too much to hinder. 

Gathering data at the summit of Cnwch Bank

As we left Cnwch Bank, we also left behind the welcome breeze and although the descent down the hill’s southerly ridge was on a beautiful green track, the lack of breeze meant that for me it was like descending in to a hot cauldron.  I felt battered and this was to continue for the next hour or so. 

The route down was beautiful; it was like descending in to summer.  Stilled mature trees canopied the land with yellowed buttercups swarming across near fields.  The only vestiges of cloud were high in the sky and delicate wisps leaving a deep blue colour dominating.  The scene was to be savoured, but it was also warm and I suffered, so much so that our plan to visit Glascwm and Black Hill later in the afternoon was shelved.  I think if I had attempted these two hills I may have ended up in serious trouble. 

Colfa Hill with conditions beginning to get uncomfortably warm

The track led down to Middle Fynnonau where we stopped and chatted to a woman, it was a welcome rest.  Beyond, the track headed through a ford with a footbridge near at hand.  The sun continued to beat down. 

The ford beyond Middle Fynnolau

Eventually the rough track merged with a narrow paved lane, this led back on to the lane where the car was parked.  Between us and it was a slight uphill, by now I was wilting under the heat and just wanted to stop and bury my head in a bucket of water. 

The Church of St David's at Colfa

The much needed rest came with the peaceful surrounds of St David’s Church.  I sat inside this building recovering a semblance of decorum and turned my brow beaten mind away from the increasing temperatures outside and just sat and slowly recovered.  Remnants of painted frescoes adorned the walls with an old skull and crossbones standing out; a sign of the inevitability of death and the hope of resurrection. 

The skull and crossbones in Colfa Church

Leaving the Church it was only a short distance to Colfa Farm where we met Jane Lloyd.  We stopped and talked with Jane for a number of minutes.  She had lived at this farm all her life with her parents moving here from Herefordshire.  She led us across the hills and named all the ones we had visited earlier in the day.  She seemed quite impressed with our route; I was tempted to say ‘so was I’. 

It was a pleasure meeting Jane and she kindly posed for a few photos just before we set off toward the awaiting car.  I so enjoy meeting people from the farming community, many have a great wealth of knowledge for the hill or mountain that they work.  This knowledge is to be savoured and also saved as it forms a part of our rich heritage and culture and spans the time between historic and present times. 

Jane Lloyd of Colfa Farm

Arriving at the car was a delight, it took an inordinate amount of time for me to change in to dry and clean clothes.  I was in no rush, I munched on an apple that Aled offered me, waved at farm vehicles as they passed on the narrow lane, luxuriated in getting my walking boots off and then feeling the warmth of the sun on my body that up until now had wilted under its heat. 

The day was rounded off with a good meal in the beer garden in the Severn Arms in Pen-y-bont, the pub where Linda and I had also eaten on my last walk a week or so ago. 

 

Survey Result: 

 

Colfa Hill

Summit Height:  532.2m (converted to OSGM15, from previous Trimble GeoXH 6000 survey)  532.2m (converted to OSGM15, from previous Leica GS15 survey)

Summit Grid Reference:  SO 19449 55397 (from previous Trimble GeoXH 6000 and Leica GS15 surveys)

Bwlch Height:  387.8m (converted to OSGM15, from previous Trimble GeoXH 6000 survey)  387.7m (converted to OSGM15, from previous Leica GS15 survey)

Bwlch Grid Reference:  SO 17968 55359 (from previous Trimble GeoXH 6000 and Leica GS15 surveys)

Drop:  144.4m (from previous Trimble GeoXH 6000 survey)  144.6m (from previous Leica GS15 survey)

Dominance:  27.16% (from previous Leica GS15 survey)


 

 

Cefn Hir

Summit Height:  510.5m (converted to OSGM15)

Summit Grid Reference:  SO 20521 55051

Bwlch Height:  495.1m (converted to OSGM15)

Bwlch Grid Reference:  SO 20261 55163

Drop:  15.4m

Dominance:  3.01%


 

 

Caety Traylow

Summit Height:  522.3m (converted to OSGM15)

Summit Grid Reference:  SO 19789 56130

Bwlch Height:  501.2m (converted to OSGM15)

Bwlch Grid Reference:  SO 19299 55578

Drop:  21.1m

Dominance:  4.05%


 

 

Cnwch Bank

Summit Height:  508.8m (converted to OSGM15)

Summit Grid Reference:  SO 18692 55406

Bwlch Height:  500.6m (converted to OSGM15)

Bwlch Grid Reference:  SO 18806 55498

Drop:  8.2m

Dominance:  1.62%


 

 

For details on the survey of Colfa Hill

 

For further details please consult the Trimble Survey Spreadsheet 

Sunday, 8 November 2015

Mapping Mountains – Trimble Surveys – Fforest Glud


09.10.15  Colfa Hill (SO 194 553)  

Colfa Hill (SO 194 553)

Colfa Hill is positioned in the heart of Radnorshire where hills stand gentle and their heathered summits are eased with a number of vehicle tracks that pass between valleys and head toward their heights.  Today we wanted to visit Colfa Hill which had been on our radar for a couple of years.  The hill is listed as having 146m of drop in the Marilyns list and c 147m in the 500m Twmpau list, this drop figure is close to the 150m required for Marilyn status, and with a map summit height of 532m and with the area of the bwlch having a 388m spot height on it that is not centralised, there was an outside chance that the hill has more prominence than currently listed.

We parked, having been given permission to do so, at the end of the narrow road that passes to the north and then east of Llyn Heilyn which is to the west of Llanfihangel Nant Melan.  It was good to be out with John and Graham again and we soon had our boots on and walking up the track and across fields following rights of way on old greened vehicle tracks.

John with level in hand on the way to Colva Hill

The weather was set fine for the day with blue sky and warmth for early October.  Cresting a small intervening pastoral ridge we continued down to cross the Gilwern Brook and then headed up the other side toward the expanse of this hill’s bwlch.

Heading toward the bwlch which is on the left of photo with trees close to it

Graham nearing the bwlch

The spot height on this bwlch appears at its eastern fringes, we started assessing this area from its west and spent quite some time laying out rows of flags slowly working our way east, with measurements taken to each five flagged row and noted.  As we progressed the land that looked as if it was rising toward our hill was in fact continuing to go downhill. 

With each reading taken by John with the level to the staff that Graham was positioning beside each flag, the area of the bwlch was mapped out and its hill to hill and valley to valley traverse slowly gave up its secrets.  I noted each height reading and after about 90 minutes we had pinpointed where the critical bwlch was positioned, this was in a boggy runnel on the eastern side of the area of the bwlch and proved to be approximately five metres away from where the 388m spot height appears on the ground.

John operating the level

Graham with the staff

As John and Graham assembled the Lerica GS15 for its hours’ worth of data collection I took a few photos with the heightened autumnal colour accentuated by the low afternoon sun.  As the GS15 gathered its allotted data we watched a farmer drive sheep down the opposite hillside, half an hour later he drove toward us and I sauntered over for a chat; Ray Rogers proved very friendly and gave out smiles in his thick Radnorshire accent, we talked about the hills, their names and his sheep.  A few minutes later and John and Graham came over and we all nattered away for ten minutes or so.

The Leica GS15 gathering data at the critical bwlch of Colfa Hill

Graham and John with Ray Rogers

Graham and John beside the Leica GS15 at the bwlch of Colfa Hill

After one hour of data were collected I positioned the Trimble on top of the GS15’s antenna and we gathered a further five minutes of data, having taken a 1.086m measurement offset between its internal antenna and the ground.  Once all the equipment was packed away we headed up the hill.

Gathering data with the Trimble at the critical bwlch of Colfa Hill

Following one of the many green vehicle tracks that criss-cross these hills, we gained height and swung left (north) as we gained the south-west ridge of Colfa Hill, this track led around Cwm Griffin and soon we were beside the trig pillar at the summit.

John approaching the summit of Colfa Hill

This summit had already been surveyed with an Abney level and the high point found to be approximately seven metres north of the trig pillar.  As the afternoon sun sank ever deeper and a cooling chill enveloped the land we took a series of measurements with level and staff and found that the Abney measurement was spot on.  Soon afterward the Leica GS15 was set up and gathering its data.

Surveying for summit position on Colfa Hill

Graham and John beside the Leica GS15 at the summit of Colfa Hill

Once an hour of data were collected the Trimble GeoXH 6000 was set up on its draughts board and sat on top of the tripod that had previously supported the Leica equipment and gathered its five minutes of data.

The Trimble gathering data at the summit of Colfa Hill

The Leica and Trimble set-up position at the summit of Colfa Hill in relation to where the trig pillar is positioned

All that remained was to pack everything away and retrace our steps down the hill.  Passing over the bwlch we could see Ray and his son beside a large sheep pen, we stopped and chatted, they were just about to separate their sheep from any lingering souls who had joined from neighbouring herds and treat them against scab.

Heading down from the hill

As the sun sank behind a hill ridge to our west the last half hour back to the awaiting car proved a slightly chilly affair with autumnal clear skies heralding the onset of another cold winter.   


Survey Result:


Colfa Hill

Summit Height:  532.2m (converted to OSGM15, Trimble GeoXH 6000)  

532.2m (converted to OSGM15, Leica GS15)

Summit Grid Reference:  SO 19449 55397

Bwlch Height:  387.8m (converted to OSGM15, Trimble GeoXH 6000)  

387.7m (converted to OSGM15, Leica GS15)

Bwlch Grid Reference:  SO 17968 55359

Drop:  144.4m (Trimble GeoXH 6000)  144.6m (Leica GS15) (Submarilyn 

status confirmed)

Dominance:  27.16% (Leica GS15)






For further details please consult the Trimble survey spreadsheet click {here}