Wednesday 28 February 2018

Mapping Mountains – Trimble Surveys – Walton Hill


29.01.18  Leopard Hill (SO 872 555) and Elbury Hill (SO 869 558)

The summit of Leopard Hill

Having visited Worcester on a number of occasions over the last two years I thought it time that I investigated the highest part of the city.  This accolade had been accorded Leopard Hill which is positioned in the eastern part of the city and is hemmed in by three B roads and a number of housing estates; thankfully the upper part of the hill has escaped development and gives a brief interlude from the concrete and brick that large conurbations bring.

Leopard Hill is given a 98m summit spot height on contemporary Ordnance Survey maps and is crowned by a metal fenced water tower.  To the north-west of the hill are further areas of land that have escaped urban housing estates, these are Elbury Hill and Gorse Hill, the latter is given a 92m summit spot height on the Ordnance Survey Interactive Coverage Map hosted on the Geograph website, whilst the former is tantalizingly also given a 98m summit spot height on this same map.  However, the summit area of Elbury Hill has a number of covered reservoirs positioned on or close to this hill’s high point and as these structures are frowned upon as far as the natural height of a hill is concerned I wanted to investigate and see if an on-site visit and a survey with the Trimble GeoXH 6000 could confirm which hill is higher.

Before detailing my visit it’s best to mention that the summit of Elbury Hill is shown with a triangular symbol on the Ordnance Survey Six-Inch map published in 1886, which is given the height of 323ft (98.5m) on the Six-Inch map published in 1905.  The latter map has a covered reservoir marked to the north of the triangular symbol, whilst the map from 1886 just has the symbol; this implies that the 323ft (98.5m) height was taken to natural ground before the covered reservoir was constructed.  The TrigpointingUK website details a block that replaced a pillar in 1970 and which is adjacent to a mast that stands in one of two covered reservoir compounds and therefore is off limits for budding surveyors, this mast is also recorded in the OS Trig Database at SO 86872 55812, unfortunately a height is not recorded for it.  The 323ft (98.5m) height would have been to the old pillar which is given the position of SO 86915 55816 in TrigpointingUK.  

Extract from the Ordnance Survey Six-Inch map published in 1886

Extract from the Ordnance Survey Six-Inch map published in 1905

I parked between the two hills just off the B 4537 Tolladine Road and walked to its high point which is where the col between the hills is positioned, and continued down the road looking for a public footpath giving access to the northern part of Leopard Hill, when found this led through a housing estate toward the upper part of the hill, with the continuation of the path beyond the houses mud splattered from the morning’s rain.

The high point of Tolladine Road

The afternoon’s forecast was good and deep grey cloud interspersed with radiant blue gave a dramatic colour to proceedings.  The muddy path led up to rougher grass and the summit area of Leopard Hill with its metal fence and squat water tower.  I walked around the compound and assessed the ground from various directions and judged land to the west of and adjacent to the structure to be the highest.

The Trimble GeoXH 6000 gathering data at the summit of Leopard Hill

Thankfully the Trimble achieved its 0.1m accuracy level before data should be logged relatively quickly, and as it beeped away gathering the allotted 300 individual data points I stood back and admired the view, which took in much of Worcester and the Malvern hills beyond.

The Trimble GeoXH 6000 set-up position at the summit of Leopard Hill

Once data were stored I retraced my inward route back to the B road and walked back up to the connecting col between the hills and followed a footpath on the right which led across Elbury Park Road and continued to a track giving access to the upper part of Elbury Hill.  On my way up I passed and said hello to a couple of dog walkers as the sky turned a menacing grey colour and which kept the sun at bay for the majority of the duration I was on top of the hill.

The track continued around the upper northern part of the hill, whilst I opted to leave it favouring wooden steps that led directly to the summit area.  There are two large fenced compounds on the summit of Elbury Hill, whilst the ground between is open.  I spent a number of minutes assessing the lay of land and having judged the high point to be on the open ground close to its periphery and only just higher than the encircling brambles, vegetation and small trees, I placed the Trimble on top of my rucksack, measured the offset between its internal antenna and the ground below and waited for five minutes of data to be collected.

Gathering data from where I judged the summit of Elbury Hill to be positioned with the southerly of the two compounds and where the high mast is positioned, in the background

During data collection I investigated the compounds, took a number of photos and admired the view overlooking Worcester with the Malvern hills beyond, I also contemplated the open ground where the Trimble was placed and wondered if the whole of this hill’s summit including the open ground consists of one big covered reservoir, or if it consists of a number of these structures, but as the majority of covered reservoirs I have seen on top of hills have been situated in fenced compounds, I thought the open ground to be an indicator that a covered reservoir is not below it.  Once five minutes of data were stored I walked the perimeter path around each of the fenced compounds, the second of which houses the high mast and OS block and which is out of bounds, and then used the wooden steps as my descent route.

Looking through the metal fence in to the northern compound

Worcester with the Malvern hills beyond

Before heading back to my car I contemplated getting a data set from the col, which would at least give a drop value for the lower of these two hills.  However, Tolladine Road was particularly busy and it would have meant placing the Trimble in severe peril, which I am prone to do on occasion, this time I was happy enough to turn my back on the col and wander down the road to my car. 


Survey Result:


Leopard Hill

Summit Height:  97.2m (converted to OSGM15)

Summit Grid Reference:  SO 87286 55551

Drop:  c 25m (col swap with Elbury Hill)

Dominance:  25.92%





Elbury Hill

Summit Height:  97.4m (converted to OSGM15)

Summit Grid Reference:  SO 86900 55854 (recommended summit relocation for qualifying Tump)

Drop:  c 53m (col swap with Leopard Hill)

Dominance:  54.84%






Although the recommendation is to swap the position of the col and therefore the drop value and status as Tump of these two hills, the height difference produced by surveying with the Trimble GeoXH 6000 is not great.  However, the resulting data is the best available at hand, with the caveat that higher ground may exist close to where the Trimble was placed on Leopard Hill and that higher ground may exist in the southern compound close to, or at the position of the high mast on top of Elbury Hill.  The added complication are the covered reservoirs on Elbury Hill and whether the open ground between the two compounds can be thought of as being natural.

Tuesday 27 February 2018

Mapping Mountains – Significant Name Changes – Y Trichant


Mynydd Bach (SJ 051 123)

There has been a Significant Name Change to a hill that is listed in the Y Trichant, with the summit height, drop and status of the hill being confirmed by a Trimble GeoXH 6000 survey conducted by Myrddyn Phillips which took place on the 26th January 2018.

The criteria for the list that this name change applies to are:

Y Trichant – Welsh hills at and above 300m and below 400m in height that have 30m minimum drop, with an accompanying sub category entitled the Sub-Trichant consisting of all Welsh hills at and above 300m and below 400m in height that have 20m or more and below 30m of drop.  The list is authored by Myrddyn Phillips and the Introduction to the list and the re-naming and publication history was published on Mapping Mountains on the 13th May 2017.

The hill is adjoined to the Y Berwyn range of hills which are situated in the south-eastern part of North Wales (Region A, Sub-Region A4), and is positioned between the Afon Banwy to the south and the Afon Efyrnwy (River Vyrnwy) to the north-east, with the A 458 road to its south-west and the small community of Dolanog which is to its east north-east. 

Mynydd Bach (SJ 051 123)

The hill appeared in the 300m P30 list on Geoff Crowder’s v-g.me website under the name of Pen-y-graig.  During my early hill listing I thought it appropriate to either invent a name for a hill, or use a name that appeared near to the summit of the hill on Ordnance Survey maps of the day.  My preference was to use farm names and put Pen, Bryn or Moel in front of them, or as in this instance, use the name of a building which I thought that of the hill.

Pen-y-graig    323m    SJ051123    125  239

This is not a practice that I now advocate as with time and inclination place-name data can be improved either by asking local people or by examining historical documents, through this form of research an appropriate name for the hill can usually be found, and in the case of this hill it was a local farmer who owns the land where the summit of the hill is situated who gave the name of Mynydd Bach.

Extract from the Ordnance Survey 1:25,000 Historical map
The local farmer is Trefor Jones who farms from Maes Celynog which is situated towards the south of the hill.  Whilst visiting this hill and its adjacent P30 I was fortunate to meet Trefor who was on his way up to the lower field of this hill in his tractor.  He stopped and we chatted for a number of minutes with him explaining that the hill is known as Mynydd Bach and it is on land that he owns having bought it off an adjacent farm.  Trefor is a Welsh speaker and gave me the translation of the hill’s name as small mountain.

Trefor Jones

Therefore, the name this hill is now listed by in the Y Trichant is Mynydd Bach and this name was derived from local enquiry.


The full details for the hill are:

Group:  Y Berwyn

Name:  Mynydd Bach

Previously Listed Name:  Pen-y-graig 

Summit Height:  324.9m (converted to OSGM15)

OS 1:50,000 map:  125

Summit Grid Reference:  SJ 05100 12325 
 
Drop:  28.5m (converted to OSGM15)


The Trimble GeoXH 6000 gathering data at the summit of Mynydd Bach


Myrddyn Phillips (February 2018)


Monday 26 February 2018

Mapping Mountains – Trimble Surveys – Y Berwyn


26.01.18  Ffridd (SJ 038 121) and Mynydd Bach (SJ 051 123)

Mynydd Bach (SJ 051 123)

Dolanog is similar to many small communities in Wales as a quiet peacefulness pervades its realm, with this peaceful tranquillity also edging to the tops above the hamlet, which is nestled beside the Afon Efyrnwy (River Vyrnwy).  Today the river gushed eastward with grey waters, with this seemingly the only thing that stirred in Dolanog.

Dolanog

I hadn’t been out on the hill with Charlie for nine months and it was good to see him again, the hills we planned on visiting were ones that he had investigated a few weeks ago and having enjoyed them he wasn’t averse to re-visiting.

Having parked and walked across the old bridge we followed the paved road heading west which soon turned in to a vehicle track beside fields recently planted with trees, these new plantations continued on the northern side of the road and track all the way from the valley below toward the higher tops above.

The route to the hills

There was a slight freshness in the air with blue skies predominating above; both were welcome as the preceding days had been damp and grey.  The track avoids the first hill skirting it on its southern side, and heads toward the connecting bwlch between the two hills; here we heard a tractor chugging up from the south, smiling at Charlie I ran off to stop it.  Its occupant; Trefor Jones, farms from Maescelynog and it was his hill that we had just passed and which we planned on visiting after the higher westerly summit had been surveyed.  Trefor told us that the hill is named Mynydd Bach, with it being purchased from Neuadd-wen a number of years ago.  After thanking him for his time we carried on following the track toward Ffridd; the first and highest hill of the day.

Trefor Jones

The track led round the northerly part of the upper section of Ffridd and so we left it to walk to the summit, which is marked by a small, old cairn.  I set the Trimble on top of my rucksack, measured the offset between its internal antenna and the highest part of the hill and once the 0.1m accuracy level had been attained, pressed ‘Log’ and joined Charlie a few metres away.  During the five minute data collection we stood and admired the late morning’s light as sun and greying cloud added atmosphere to the scene.

Gathering data at the summit of Ffridd

As the Ordnance Survey Interactive Coverage Map hosted on the Geograph website gives a second top as 1m lower than the cairned summit, we headed over to it once the Trimble had gathered its allotted five minutes of data.

Gathering data at the 328m map heighted lower summit of Ffridd

Although this second top didn’t have the sweeping westerly views of the cairned summit it was crowned by an attractive small rock outcrop and as the Trimble quietly beeped away gathering its data, Charlie headed off to investigate the southerly outlying top which we both concluded was lower than where the Trimble was presently gathering its data.

Charlie admiring the view to the west

The 330.6m cairned summit of Ffridd from the 328.5m rock outcrop summit

Once the Trimble was packed away I joined Charlie and we then headed toward the inward vehicle track back toward the connecting bwlch between the two hills.  We’d assessed this from the track on our inward route and its southerly part was decidedly watery, enough so that even with wellies it would be a treacherous undertaking attempting to gather data from its depths, thankfully the ground slowly rose to the north and we followed the minor paved road that heads over this bwlch from south to north, to where dryer ground existed indicating that this was the higher part of the area of the bwlch. 

Looking east from the hills above Dolanog

With the Breiddin beyond

I took two data sets at this bwlch, both from its northern periphery, one amongst rough grass beside its bog and the other on the edge of the minor road, once data were stored we continued toward the summit of Mynydd Bach.

Gathering data at the critical bwlch of Mynydd Bach

As we ascended over closely cropped grass toward the summit of Mynydd Bach I occasionally turned around and looked back at the expanse of bog that makes up the connecting bwlch and even though eyesight alone is not ideal for judging either height difference or the upward / downward lay of land, the upward motion of this bwlch headed northward toward where the Trimble had been placed.

Thankfully the summit of Mynydd Bach is easily found as rising ground leads to a small embedded rock whose uppermost part just breaks the soil and grass, and with the area of the summit having no other discernible bump I aligned the Trimble with the highest part of the small rock and waited for the allotted five minute data set to be gathered.

Gathering data at the summit of Mynydd Bach

Before re-joining the vehicle track we headed further east to the end part of the upper ridge of Mynydd Bach, by now the predicted cloud build up had materialised and the sunlight that had given us striking colour had dulled.  The vehicle track led on to the upper part of paved road which took us down toward the Afon Efyrnwy and the car park in Dolanog.

   

Survey Result:



Ffridd

Summit Height:  330.6m (converted to OSGM15, Trimble GeoXH 6000) (significant height revision)

Summit Grid Reference:  SJ 03897 12140 (Trimble GeoXH 6000)

Bwlch Height:  c 253m (interpolation)

Bwlch Grid Reference:  SJ 03041 12323 (interpolation)

Drop:  c 78m (Trimble GeoXH 6000 summit and interpolated bwlch)

Dominance:  23.48% (Trimble GeoXH 6000 summit and interpolated bwlch)







Summit Height:  324.9m (converted to OSGM15)

Summit Grid Reference:  SJ 05100 12325

Bwlch Height:  296.4m (converted to OSGM15)

Bwlch Grid Reference:  SJ 04661 12268

Drop:  28.5m

Dominance:  8.79%










Sunday 25 February 2018

Mapping Mountains – Trimble Surveys – Stiperstones


23.01.18  Hazler Hill (SO 464 928), Ragleth Hill (SO 454 921) and Ragleth Hill (SO 451 917)

Ragleth Hill (SO 454 921)

Having seen the forecast I did wonder if it was wise going out as it seemed almost guaranteed that we were going to get wet, and however much our beautiful green land relies upon the wet stuff it is the one type of weather that I make a concerted effort to avoid.

I was out with Mark today and we headed east in to Shropshire and the hills around Church Stretton, with a route taking in Hazler Hill and Ragleth Hill planned, Mark had visited the latter but was good enough to repeat his ascent, by visiting these hills we also hoped to be in the rain shadow of the higher hills above Church Stretton to our west, as it turned out we picked our hills wisely and got away with only a few spots of rain mid-afternoon, although it was a bit blowy to say the least.

We parked close to the centre of the town and crossed the busy A49 road and picked up the public footpath that leads southward toward the col between Hazler Hill and Ragleth Hill.  With the mast atop the former an ever present indicator of the steepness of these hills.

The mast atop Hazler Hill

The early morning’s rain had swept east, with another front predicted for the afternoon, and therefore the going under foot was soggy as we made progress near to Plocks Coppice through gentle deciduous woodland.

The upper part of the footpath leading to the minor lane

The footpath led to a minor lane where the view toward the east opened up, dark skies predominated with an occasional flash of sunlight highlighting the land.  We followed the lane north-eastward to the access track to the high mast and used this to reach the summit area.

Dark skies to the east

Further north the shapely profiles of Caer Caradoc and Hope Bowdler Hill looked inviting, both have been Trimbled as have the bulk of P30s over 400m in these parts.

Caer Caradoc

Hope Bowdler Hill

As we crested the area of the summit the wind blew from the south, it was unusually mind for this time of year but the wind would remain with us on the tops for the rest of the walk.  The trig pillar atop Hazler Hill is not positioned at the high point; this is further south-west beside the fenced-off area that houses the mast.

Hazler Hill with the trig pillar and high mast with the summit to the left of the fenced-off area

It took the Trimble an inordinate amount of time to achieve the 0.1m accuracy level before data should be logged, I’d propped it on top of my rucksack which was positioned flat on the ground, and wedged it in position with two rocks, otherwise it may have been blown off.  Once data were gathered and stored we retraced out route back on the access track and followed the lane south-west toward the public footpath gaining the north-eastern slopes of Ragleth Hill.

Gathering data at the summit of Hazler Hill

These hills are distinctive and give a sense of being separate, with each affording good views of the other.  The route up Ragleth Hill proved steep, we made good progress and as the higher ridge was reached the wind blew directly in to our faces, from here a path leads all the way to the summit, which is comprised of grass about 5 metres from a small embedded rock.

Hazler Hill from the ascent of Ragleth Hill

Caer Caradoc from the ascent of Ragleth Hill

As I set the Trimble up Mark continued on the ridge to the relative shelter of the connecting col to a potential 390m Double Sub-Four which I planned on surveying.  The wind was blowy on top of Ragleth Hill and once the measurement offset had been taken I wedged the equipment in place with the two small rocks which I’d brought from the summit of Hazler Hill.

Gathering data at the summit area of Ragleth Hill

Mark heading to the relative shelter of the connecting col to the potential 390m Double Sub-Four

This was the high point of the day’s walk and a summit that had previously been surveyed by Alan Dawson using his Leica RX1250, so it’ll be interesting to compare the results.  Once the Trimble was packed away I joined Mark at the col and as I set the Trimble up to gather another five minute data set he headed for the summit of the potential sub to assess the lay of land.

Gathering data at the col of the potential 390m Double Sub-Four

By the time the Trimble had collected five minutes of data the rain had arrived, it blew in quickly from the south, where the sky was now slate grey, the land to the west and east looked particularly murky and I thought we were going to get a good drenching, however the few spots that fell were quickly swept away leaving us intermittent light drizzle when down in the valley, otherwise it remained dry on the tops, we were indeed fortunate.

As I joined Mark on top of the potential sub the wind howled across its summit, Mark quickly pointed to the highest rock and shot down the continuation of the ridge seeking a semblance of shelter leaving me to somehow balance the Trimble atop the high point without it moving for the five minutes of data collection I usually allocate.  This proved a difficult task as the wind increased in intensity and kept howling for the duration I was on the summit. 

It took three attempts for me to gather data, I eventually wedged the rocks either side of the Trimble whose internal antenna was aligned with the high point of the highest rock, and then proceeded to crouch below it whilst holding one rock in place and also the end part of the equipment. 

Gathering data at the summit of the potential 390m Double Sub-Four

During this process I counted each second, occasionally timing my count with the beeps emanating from the Trimble indicating each data point that was gathered, these are collected per second, and with five minutes of data allocated I needed to reach the magical 300 before switching the equipment off, unfortunately the wind was so fierce I only occasionally heard the beeps from the Trimble and therefore spent my time hunkered under it counting silently before it was time to close it down and store the data.  I quickly took a few photos before the Trimble was blown in to Herefordshire and then walked down the steep southerly ridge to join Mark.

Once out of the gale we followed the path down to the A49 road where the old bridge led us in to Little Stretton, passing on the way a memorial to Crag Bullock entitled Country Blood, and which has been transcribed by Mark and appears below.


Country Blood

I am of the countryside
Carved out of the oaktree bark
And I am of the wild free wind
That bears the soaring lark.
Part of the upturned earth am I,
One with the cornfield sea,
And I exist in the quiet green hill
And it exists in me.


Here all the dainty weeds are mine
That blows along the way,
And all the little resting things
Whose heart beat for a day.
My peace is where the velvet dew
Sleeps under hanging mists;
Where the cavernous forest deeps and dims
My secret soul exists.


Poem, by anon, inscribed on the grave of Craig Bullock, carpenter
‘tragically killed’, aged 30, on 4th October 2002

Below Ragleth Hill, Shropshire, at grid ref. SO 44577 91487


The memorial to Craig Bullock

It wasn’t far to the car from the delightful narrow lanes of Little Stretton, although my old body suffered and just wanted to sit down.  This I did after changing in to clean clothes back at the car, as we walked in to town for an assortment of goodies at a very good café; yummy!

LIDAR image of Hazler Hill (SO 464 928)

Postscript:

Since the survey of these hills LIDAR has become available.  The LIDAR (Light Detection & Ranging) technique produced highly accurate height and positional data that is now freely available for England and Wales.  Consequently the numerical details for these hills have been analysed using this technique, resulting in the LIDAR height and position for some of these hills being prioritised.



Survey Result:



Hazler Hill

Summit Height:  346.7m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SO 46469 92873 (Trimble GeoXH 6000)

Col Height:  307.8m (LIDAR)

Col Grid Reference:  SO 46226 92445 (LIDAR)

Drop:  38.9m (Trimble GeoXH 6000 summit and LIDAR col)

Dominance:  11.22% (Trimble GeoXH 6000 summit and LIDAR col)





Ragleth Hill

Summit Height:  397.3m (converted to OSGM15, Trimble GeoXH 6000)  397.5m (Leica RX 1250)

Summit Grid Reference:  SO 45403 92098 (Trimble GeoXH 6000)  SO 45406 92101 (Leica RX1250)

Col Height:  256.2m (LIDAR)

Col Grid Reference:  SO 46809 93242 (LIDAR)

Drop:  141.3m (Leica RX1250 summit and LIDAR col)

Dominance:  35.55% (Leica RX1250 summit and LIDAR col)





Ragleth Hill

Summit Height:  391.1m (converted to OSGM15)

Summit Grid Reference:  SO 45103 91746

Col Height:  372.1m (converted to OSGM15)

Col Grid Reference:  SO 45262 91867

Drop:  19.0m

Dominance:  4.85%