Mapping Mountains – Trimble Surveys – Carnedd Wen

01.03.21  Gaer Fawr Hill (SJ 223 129)

Gaer Fawr Hill (SJ 223 129)

Glorious early spring sunshine and warmth has dominated over the last two days, but at this time of year conditions can be easily transformed and this morning I set out from my home following the canal towpath as mist and murk hugged the waters and surrounding countryside. 

Misted scene beside the canal towpath

Mist can bring a beauty all its own and as I followed the Rhallt and then Gungrog Fawr Lanes steeply uphill I stopped occasionally to just listen.  Without a breath of breeze and no extensive view one’s world becomes enclosed and mine this morning concentrated on the delicate ebb of a slow flowing brook, whilst bird song wafted from a near hedgerow and almost silent drops of moisture fell from overhanging trees scattering as they did so on the muddied track at my feet.  It was a morning to savour, albeit a bit chilly compared to the last couple of days. 

I was at the crossroads bisecting the Gungrog Fawr Lane and Windmill Lane at 9.15am and waited for Linda to emerge out of the mist five minutes before our pre-arranged meeting time.  Good with time this girl is! 

Our plan for the day was to follow lanes and footpaths down in to Guilsfield and then head up Gaer Fawr Hill, which I’d visited once before in August 2015 along with Alex Cameron during a bagging bonanza of local hills.  It was then awash with late summer green, today the mist lingered. 

Prior to this visit I’d analysed the hill’s numerical details with LIDAR.  Producing an accurate height and position for its connecting bwlch and a height and position for its summit, with the LIDAR summit position being 18 metres from where the Trimble gathered data on my previous visit.  I’d come prepared with ten figure grid references for each and hoped that the lack of summer growth would help in determining the hill’s high point. 

LIDAR image of Gaer Fawr Hill

We followed the paved road past Trelydon Hall and continued toward a quiet lane leading in to Guilsfield, here we diverted to a footpath leading in to a wood which led us to Glanllyn Pool.  This was a surprise as my Ordnance Survey map doesn’t show the pool, but there it was bathed in morning mist resembling an image from the Florida Everglades. 

Glanllyn Pool

Surprises are often welcome additions to any walk and Glanllyn Pool was certainly so.  We happily sauntered beside its waters for ten minutes across the greened and partly muddied walkways and duckboards leading to one of the village’s housing estates.  I then wanted to take us in the wrong direction, which I’m prone to do on occasion. Even with an OS map in hand my navigation skills and sense of direction can be found wanting.  Linda recognised one or two houses and a quick enquiry with a postwoman put us on the right route toward our hill. 

Gaer Fawr Hill is impressive; however its ancient earthworks are now immersed in woodland which although attractive has distracted from the earthen embankments and ditches.  The walk to its summit is enjoyable though and today the misted scene added tranquillity to the already quiet nature of this part of Wales. 

Heading up Gaer Fawr Hill

There are a number of paths leading up to the semi-open summit area and once there I set about determining its high point.  I collected data from two points whilst Linda sat patiently on a tree stump as the Trimble ever so slowly crept down to the 0.1m accuracy level before data should be logged.  By the time the second data set was gathered and stored the mist had risen and sun was breaking through the overhead grey cloud cover. 

The summit area of Gaer Fawr Hill

Once the Trimble was packed away we continued over the hill to visit the terracotta wild boar which is an enlarged replica of a bronze wild boar found on the hill during excavation.  Beyond the terracotta piggie we followed a steeply descending path that eventually contoured the lower southerly slopes before finding ourselves back on our inward lane. 

The terracotta wild boar

Glimpse of sunshine on the descent from Gaer Fawr Hill

We then retraced our steps back to the delights of Glanllyn Pool, followed by the Windmill Lane just beyond Trelydan Hall, meeting and chatting with a myriad of dog walkers, goats, horses and of course the occasional sheep! 

The delights of Glanllyn Pool

All that remained was the walk back on public footpaths across fields adjacent to the Windmill Lane to the top of the Red Bank and then down through the grounds of St Marys toward the centre of Welshpool.  It proved yet another excellent little expedition, this time to the wild and salubrious surrounds of Guilsfield.  

 

Survey Result:

 

Gaer Fawr Hill

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

Summit Grid Reference:  SJ 22394 12995 (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 Hill

For details on the 3^rd visit to Gaer Fawr Hill

 

For further details please consult the Trimble Survey Spreadsheet