Mapping Mountains – Trimble Surveys – Carnedd Wen

 

20.11.25  Gaer Fawr (SJ 223 129, previously Trimbled)

Gaer Fawr (SN 223 129)

Gaer Fawr stands as a large mound of a wooded hill on the periphery of Guilsfield.  The trees hide its true significance as one of Wales’ great ancient hill forts.  When occupied it had up to five lines of ramparts, with some 8m in height.

The wood surrounding the hill is now managed by the Woodland Trust and today’s visit was with my cousin Lynn.  Since our last visit in May 2021, Lynn had donated a large sum to the Woodland Trust from a trust fund set up in memory of her late husband; Dave.  Part of the donation went toward installing a bench overlooking the eastern aspect of the hill toward Cefn Digoll off in the distance.  Therefore, as well as enjoying Lynn’s company whilst taking in a small walk, she wanted to show me the bench set up in Dave’s memory.

Having left my car in the parking area beside a small quarry we headed back down the narrow lane that leads toward the south-westerly lower part of the hill.  The weather was set fine, albeit with a chilled easterly breeze.  However, during our walk we were sheltered from this in the wood.

There are a number of paths through the wood, all seem to connect with ones leading to the summit which I’d previously Trimbled.  Our route for the day led back down the narrow road to a gate giving access to the lower eastern part of the wood. 

Lynn on the path heading through the wood

It was good to be out with Lynn again, a person whose company I’ve enjoyed on small walks over recent years.  The path circled the easterly part of the wood, gaining height as it did so, before swinging up in to the canopy of trees that shone dappled light whenever the sun broke through intermittent cloud. 

The bench set up with one of Lynn's donations to the Woodland Trust

Our route led us straight to the bench.  It was an ideal place to stop and rest.  From this position a gap in the trees looked out toward the east.  Just behind us another path led up to connect with one of the main routes to the summit.  The bench had been placed in a quiet spot, one for rest and contemplation.  A small plaque on it had an inscription from one of Lynn’s favourite poems which she read for me; Fern Hill by Dylan Thomas, ‘and once below a time I lordly had the trees and leaves’.  I took a few photos before we left to head up the path toward the summit. 

The plaque in memory of Lynn's late husband

Although the summit area is open there is no extensive view due to surrounding trees.  However, it is a beautiful place to visit and especially so in May when blue bells adorn the ground. 

The summit of Gaer Fawr (SJ 223 129)

We both wandered, me enjoying the dappled low light casting deep shadow and emerald colour through the trees and Lynn looking out through the trees to the lands beyond.  We left heading down to visit the large terracotta wild boar that commemorates the bronze boar helmet found at this site that is positioned near the top of the ancient north-east entrance. 

The terracotta boar

Leaving the wild boar we took the path down, opting for the longer route that contours the lower part of the wood leading back to the small quarry and the awaiting car.  By the time we arrived the temperature had chilled with late afternoon heralding another cold frost encrusted night. 

    

Survey Result: 

 

Gaer Fawr (significant name change)

Summit Height:  217.6m (converted to OSGM15, from previous Trimble GeoXH 6000 survey) 

Summit Grid Reference:  SJ 22394 12995 (from previous Trimble GeoXH 6000 survey) 

Bwlch Height:  138.7m (LIDAR)

Bwlch Grid Reference:  SJ 21991 13145 (LIDAR)

Drop:  78.9m (Trimble GeoXH 6000 summit and LIDAR bwlch)

Dominance:  36.26% (Trimble GeoXH 6000 summit and LIDAR bwlch)

 

 

For details on the 1^st survey of Gaer Fawr

For details on the 2^nd survey of Gaer Fawr

For details on the 3^rd visit to Gaer Fawr

 

 

For further details please consult the Trimble Survey Spreadsheet

Mapping Mountains – Trimble Surveys – Carnedd Wen

30.04.25  Castell Dolforwyn (SO 151 950) 

Castell Dolforwyn (SO 151 950)

With the weather set fine, my cousin Lynn, wanted to visit Castell Dolforwyn.  We’d spoken about the castle on a number of occasions over recent years, but up until now had not fixed a date to visit.  It was going to be a family outing as we had mentioned this to another cousin; Thelma, and she also wanted to visit.

It proved an extremely warm day and especially so during the afternoon.  We set off walking at 2.00pm from the small car park directly east of the summit.  It’s only a short walk from here to the remains of the castle, but today with the heat of the afternoon it was going to be a slow plod to the top. 

Information board giving detail of the castle's construction

Llywelyn ap Gruffydd built the castle in 1273 on the Welsh side of the Afon Hafren (River Severn), with Montgomery castle a few miles away on the English side of the river, with this being part of the lordships associated with the English crown.

Its occupation by Llywelyn was short lived, as defiance toward the English crown resulted in a siege, with its surrender in 1277.  Afterward it was occupied and reinforced by Marcher Lord Roger Mortimer, before falling in to disrepair and abandonment in the 14^th century.  Today it stands on a quiet Welsh hill top looking out toward border country. 

Information board giving detail of the later renervation

On my previous visit I had Trimbled the summit, therefore today was purely set aside for an afternoon with my cousins, with good conversation and lots of laughs.  A steep track leads from the car park toward a gate and an earthen track beyond, thankfully the majority of which was in shade.  The dappled light and increasing warmth gave a Mediterranean feel to the whole walk. 

The path leading to the old entrance gate

Reaching the outer perimeter of the castle a grassed bank leads through what was once the gateway entrance, to the remaining walls and enclosed rooms within.  Today we had the castle to ourselves for the majority of our visit, with the only other visitors being a mother and her two young children, who were on holiday from Belgium exploring Wales for the week in a large camper van.  They had visited the Gower, Pembrokeshire, Anglesey, Yr Wyddfa and were heading down to Brecon before flying home from Bristol tomorrow morning.  They had certainly picked a glorious week to visit. 

Thelma beside the wall

Having roamed the interior of the castle we did a loop of the exterior walls before heading back inside the castle remains, where we found a suitable place to sit and relax in shade away from what was proving a quite ferocious sun.  We remained here for about 20 minutes, cooling down and chatting. 

Lynn admiring the view

All that remained was a steady walk back down our inward route to the awaiting car, where I changed from walking boots to sandals before driving the short distance back to Welshpool. 

 

Survey Result:

 

Castell Dolforwyn (significant name change)  

Summit Height:  228.5m (converted to OSGM15, previous Trimble GeoXH 6000 survey) (significant height revision)

Summit Grid Reference:  SO 15189 95016 (previous Trimble GeoXH 6000 survey)

Bwlch Height:  188.1m (LIDAR)

Bwlch Grid Reference:  SO 14988 95278 (LIDAR)

Drop:  40.4m (Trimble GeoXH 6000 summit and LIDAR bwlch)

Dominance:  17.68% (Trimble GeoXH 6000 summit and LIDAR bwlch)

                                       

 

For details on the summit survey of Castell Dolforwyn

For further details please consult the Trimble Survey Spreadsheet 

Mapping Mountains – Trimble Surveys – Mynydd Epynt

 

02.11.24  Cae Gwar y Tŷ (SO 035 495) 

LIDAR image of Cae Gwar y Tŷ (SO 035 495)

Today, Charles and I attended the funeral of Moira Brown in Builth Wells.  Moira was married to Iain for 54 years, and as well as showing our respect to Moira it was also a gesture of support on our part to Iain, who for many years was a stalwart of the hill bagging community.  After the funeral we gathered in the Greyhound Hotel for food and conversation.

Before heading back to Welshpool we ventured to the hills.  Over the last week a high pressure system had been firmly stuck over the country, giving settled, albeit grey skies with little direct sunshine.  Such conditions can give cloud inversions on the higher hills, but can also give murky conditions with cloud nestled on the lower hills.  We planned on doing two small walks, with our second walk taking in a hill listed as a Pedwar, which is in the 400m height band, and thankfully on our approach to Builth all such hills were clear of cloud.  Our first walk took in a hill lower in height and with only a slight diversion on a narrow lane; it was on our way to the higher hill. 

Just sufficient space off the narrow lane not to obstruct other vehicles

The Tithe map gives the name of the field where the high point of this hill is situated as Cae Gwar y Tŷ.  A fine field name and one that is appropriate to use for listing purposes.  We wanted as quick an ascent as possible as daylight hours were quickly fading, therefore having LIDAR’ed the hill I decided that although I had the Trimble, I would forgo surveying its summit. 

Charles approaching the summit

The high point of the hill is positioned close to a minor road and in the main protected from any direct ascent from its east by hedges.  However, there is now a copse of woodland that stretches from the lane adjacent to grazing fields toward its summit.  The entrance to the woodland is open and opposite there is just enough space to pull a car off the lane on to the grass verge.  This was our starting point. 

The Trimble GeoXH 6000 positioned at the summit of Cae Gwar y Tŷ

It only took a few minutes to get our gear together and enter the wood.  Low branches were avoided as we made our way through and between the trees, and we were soon straddling the low hung barb wired fence and standing on the summit of the hill. 

Charles beside the Larch tree near the summit

Although not planning to Trimble the summit I set the equipment up on my rucksack to at least take a few photos of it.  During this Charles headed in to the wood for our descent, but before heading down, he stood beside an elegantly coloured Larch tree for the customary autumnal photograph. 

Heading down through the wood to the lane below

All that remained was the walk back through the wood to the awaiting car, avoiding any low hanging branches on our way.  It had taken seven minutes to visit this hill and that included taking a number of photographs whilst on or near the summit. 

 

Survey Result:

 

Cae Gwar y Tŷ (significant name change)      

Summit Height:  232.8m (LIDAR) (significant height revision)

Summit Grid Reference:  SO 03502 49537 & SO 03504 49535 (LIDAR) (summit relocation)

Col Height:  198.4m (LIDAR)

Col Grid Reference:  SO 03391 49083 (LIDAR)

Drop:  34.4m (LIDAR)

Dominance:  14.786% (LIDAR) 

 

 

For further details please consult the Trimble Survey Spreadsheet

 

 

Mapping Mountains – Trimble Surveys – Carnedd Wen

06.09.23  Castell Dolforwyn (SO 151 950) 

Castell Dolforwyn (SO 151 950)

Castell Dolforwyn sits atop a hill that from the near main road is shrouded by trees.  I had only visited once before; in February 2004 when combining this hill with a number of other P30s to its north-west.  Other than prior knowledge of its position and/or the small signpost pointing toward it from the road to its east, it would be all too easy not to know that one of Wales’ most important ancient castles is positioned near-by. 

Text from the information board at the small car park

The castle was built in 1273 by Llywelyn ap Gruffydd on the Welsh side of the Afon Hafren (River Severn), with the castle at Montgomery only a few miles away on the English side of the river and very much a part of the lordships associated with the English crown.

The information board beside the narrow lane leading to the small car park

Its occupation by Llywelyn was short lived as defiance toward the English crown resulted in a siege and following surrender of the castle in 1277.  It was then occupied and reinforced by Marcher Lord Roger Mortimer, before falling in to disrepair and abandonment in the 14^th century.  Today its remains are evocative, standing as one of the last vestiges of Welsh Princedom in this part of the country. 

A brief history of the castle

With business to attend to in Newtown and the prospect of a forested top to visit this upcoming Saturday, and the forecast for warm conditions I thought a small walk to a single hill on my way home to Welshpool was in order, and Castell Dolforwyn ticked all boxes.

I pulled up at the small parking area to the east of the summit and was walking by 10.15am.  The path from this direction leads through a gate and then steeply up a track with embedded stone giving grip for vehicle access to Yewtree Cottage, which could be seen clinging to the hillside from the car park below. 

One of many butterflies flitting about in the morning's sun

The hedgerows were awash in greenery with a myriad of butterflies flitting about in the morning sun.  The track veered leftward and then gradually gained height until beside the cottage, from here a gate accesses the upper track which eventually leads to the remains of the castle. 

The track leading to the castle

The sky was ablaze with blue as I approached the stone work of the exterior walls, it was already warm and I was glad that the uphill was now over with.  Prior to the visit I had used LIDAR to determine the height and position of the summit and its connecting bwlch and had come prepared with the relevant ten figure grid references.

LIDAR gives two high points 1.1cm apart in height.  The first one that I approached looked higher.  However, it is reported that the upper hill was levelled to accommodate the building of the castle, so any semblance of a natural high point is only what remains today.  Before positioning the Trimble to gather its first data set I wandered parts of the castle and looked back toward the spot the Trimble was now placed upon, and it was soon set to gather its allotted data. 

Gathering data at the summit of Castell Dolforwyn

This high point matched the LIDAR co-ordinates for the summit.  As the Trimble quietly beeped away gathering its all-important summit data I sat on one of the stone walls and waited for the five minutes of data to be stored.

Once data were gathered and stored I closed the equipment down and immediately activated it again as I headed toward the second LIDAR top, this proved to be on a gravelled section at the north-easterly part of the castle, I quickly dismissed this as unnatural and backtracked to a slight grassy rise between the two points. 

LIDAR summit image of Castell Dolforwyn

This second position is given lower by LIDAR, but now here I wanted a comparison of Trimble data with the gravelled section dismissed as a recent man-made construct.  During data collection the castle surrounds remained quiet, with only the occasional sound of a bird and the tree scampering of a squirrel. 

Gathering data at the second point surveyed with the Trimble GeoXH 6000

Once the equipment was packed away I wandered around the castle, reading the various information boards as I did so.  Leaving the inner castle I then walked the perimeter of the exterior walls at their immediate base.  This gave a good and different perspective to the castle and I would recommend doing this to any visitor. 

Part of the exterior wall

An information board in the interior of the castle

The south-west corner of the castle

By the time I left and headed back down the rack it was getting increasing warmer, but I was in no rush and the going was easy.  Back at my car I talked with a Dutch couple who were touring Wales for the week.  We chatted for ten minutes or more before they set off up the steep track toward the castle; I recommended taking lots of water as it was now decidedly hot.  

 

Survey Result:

 

Castell Dolforwyn (significant name change)

Summit Height:  228.5m (Trimble GeoXH 6000) (significant height revision)

Summit Grid Reference:  SO 15189 95016 (Trimble GeoXH 6000)

Bwlch Height:  188.1m (LIDAR)

Bwlch Grid Reference:  SO 14988 95278 (LIDAR)

Drop:  40.4m (Trimble GeoXH 6000 summit and LIDAR bwlch)

Dominance:  17.68% (Trimble GeoXH 6000 summit and LIDAR bwlch)

                                       

For details on the 2nd visit to Castell Dolforwyn

For further details please consult the Trimble Survey Spreadsheet

 

 

  

Mapping Mountains – Trimble Surveys – Carnedd Wen

 

13.07.23  Yr Allt (SJ 242 100, previously Trimbled) 

Yr Allt (SJ 242 100)

It was my pleasure today to join Sarah Kerr on part of her Offa’s Dyke walk.  Sarah had contacted me a few weeks ago and asked if I would like to join her for a few hours as she was walking part of the long distance footpath north of Welshpool.

Considering how wet recent days have been we were ever so fortunate with the weather as although an occasional slow moving shower was forecast for parts of Wales, any grey cloud that materialised did not develop in to rain and our walk remained dry. 

Sarah Kerr

I met Sarah at 8.30am on the Rhallt Lane outside the recently built and large property where she overnighted.  The morning was beautiful with blue sky and the hint of warmth in the air.  It was good to see her as the last time our paths crossed were a number of years ago when trips to Welsh islands and lighthouses were organised.

Prior to meeting I suggested the possibility of including an ascent of Yr Allt from the Rhallt Lane and dropping off the hill back on to the canal towpath which hereabouts also forms a part of Offa’s Dyke footpath.  Sarah was on for this, therefore after pleasantries we walked up the steep lane chatting about all manner of things.  The conversation must have been good as even though I’d been this way a number of times over recent years we overshot the footpath I planned for us to follow.  This meant we remained on the lane as it turned in to a track and we followed it to its high point. 

In the field leading toward the trig pillar

At the end of the track a footpath continues through undergrowth to connect with a forest track, however we now headed to our right on to a steepening field where wild flowers predominated, with a plethora of butterflies flitting this way and that in the warmth of the strengthening sun. 

Approaching the trig pillar

This part of the field forms a ridge that leads ever upward to where the triangulation pillar sits confidently looking north-eastward out toward the Breiddin and the higher hills to the west.  The western horizon was dominated by the Y Berwyn ridge with the higher Aran also on show, with their elongated ridge still battling with wisps of cloud which no doubt would soon be burnt off. 

The distant Y Berwyn

Leaving the trig pillar we lost height heading toward the corner of the lower field, where a stile gives access to another field leading past the large mast that can be seen from many miles away signifying the summit area of this hill.  Shortly beyond is the high point, it doesn’t afford the view that the ground beside the trig pillar does, but it is the summit and therefore with my bagging hat on it had to be visited. 

Sarah at the summit of Yr Allt

To get on to our descent route we now doubled back to the trig pillar and followed the ridge downward past pheasant pens and the Gamekeepers Cottage at the end of the forest track.  Down we went heading toward the Coppice Cottage where many a year ago I used to live.  However, before the cottage is a forest track on the right that heads down through the wood.  I had always wanted to investigate this track and see where it leads.  Having already mentioned this to Sarah she had no objection to us investigating this route.

The track led us down through the wood and seemed to grind to a halt where summer undergrowth of nettles and brambles then took over.  Just below us was a high pheasant fence which conveniently for us had been flattened due to a tree bow falling on it.  However, between us and it was all manner of debris which entailed an assault course to get through, which we eventually did, emerging on to an open field and with the aid of mapping on Sarah’s mobile phone we were soon directed down the field to a footbridge crossing the canal.

After crossing the footbridge we had one barb wired fence to negotiate before reclaiming the canal towpath.  Our onward routes now headed in opposite directions, Sarah farther northward following the footpath of Offa’s Dyke and southward for me back toward Welshpool. 

Sarah heading off on the canal towpath to continue her Offa's Dyke journey 

Before heading our separate ways we had a hug and I thanked Sarah for the invite to join her.  It had been an immensely enjoyable few hours with good company, good conversation and a hill thrown in for good measure!

Survey Result: 

 

Yr Allt

Summit Height:  231.3m (converted to OSGM15, from previous Trimble GeoXH 6000 survey)

Summit Grid Reference:  SJ 24240 10005 (from previous Trimble GeoXH 6000 survey)

Bwlch Height:  125.9m (LIDAR)

Bwlch Grid Reference:  SJ 21855 08773 (LIDAR)

Drop:  105.4m (Trimble GeoXH 6000 summit and LIDAR bwlch) 

Dominance:  45.57% (Trimble GeoXH 6000 summit and LIDAR bwlch)

 

 

For details on the first Trimble GeoXH 6000 summit survey of Yr Allt

For details on the second Trimble GeoXH 6000 summit survey of Yr Allt

For details on the Trimble GeoXH 6000 bwlch survey of Yr Allt

For details on a third visit to the summit of Yr Allt

For details on a fourth visit to the summit of Yr Allt

For details on a fifth visit to the summit of Yr Allt

 

 

For further details please consult the Trimble Survey Spreadsheet