Mapping Mountains – Trimble Surveys – Stiperstones

24.09.16  Caer Caradoc (SO 477 953, previously Trimbled), Willstone Hill (SO 485 943), Hope Bowdler Hill (SO 479 940) and Helmeth Hill (SO 469 938, only col Trimbled)   

Willstone Hill (SO 485 943)

The Shropshire hills offer so much, with their quiet beauty being a joy to re-visit.  The heartland of these hills is centred on the small market town of Church Stretton, and it here that Mark had suggested to meet; also joining us was Bob Kerr, who was driving north from Southampton and kindly taking me to Scotland afterward for Rick and Jen’s celebratory completion of the Marilyns.

Leaving two cars in the town I then drove northward to squeeze my car beside a gate on a track that gave us access to Caer Caradoc, which is one of the gems of upland Shropshire.

This chosen route gave us access to the north ridge of the hill and as height was gained The Lawley stood proud with the flat plains beyond only reaching skyward again with the up thrust of The Wrekin, which proved an ever present distant pyramidal profile placed on the horizon.

The Lawley (SO 494 974)

Mark and Bob on the way up Caer Caradoc

Thankfully the forecast was for dry, albeit gusty conditions and as we crested the upper part of Caer Caradoc the wind blasted across the landscape.  The customary summit photographs were taken with Bob adopting a celebratory pose as he ticked off another Marilyn.

At the summit of Caer Caradoc

Dropping off the hill south-eastward gave us shelter and good paths led us down toward the col of Hope Bowdler Hill, which is listed as a Hump and Four, and which was our next main hill of the day.  I’d previously surveyed Caer Caradoc with Charlie Leventon in March 2015, so decided to concentrate on summits and cols that had not yet been Trimbled.

Willstone Hill and Hope Bowdler Hill from the descent of Caer Caradoc

Reaching the col I set the Trimble up placed on top of my rucksack to give it elevation above its immediate surrounds, quickly measured a 0.44m offset between its internal antenna and the ground at the base of the rucksack and once the 0.1m accuracy level was attained, pressed ‘Log’ and scampered off to join Mark and Bob who were happily munching on their lunch.

Gathering data at the col of Hope Bowdler Hill

Above us were the gently sloped upper reaches of Hope Bowdler Hill and its lower neighbour; Willstone Hill, which is listed as a Sub-Four with the minimum qualifying drop of c 20m.  It seemed a shame to miss out on giving this hill an accurate height and drop and so after the col data was gathered we headed its way.

Willstone Hill is crowned by rounded heathland with a volcanic plug at its far north end, the high point of which clearly vied for being the summit of the hill.  Bob skipped up it and conducted a quick precision survey comparing its height against that of the heathland at its base, it was decided to Trimble both, and as Mark and Bob waited patiently I positioned the Trimble aligned with the high point of the rock outcrop and as the strength of the wind was somewhat strong I attached its dog lead which I held as the five minutes of data were gathered.

Bob on the top of the relocated summit of Willstone Hill

The art of precision surveying

The Trimble attached to its dog lead at the summit of Willstone Hill

Afterward I set the Trimble up on my rucksack on the summit area of land near the base of the rock outcrop and as the five minutes of data were collected Mark and Bob headed down to the adjoining col seeking shelter out of the wind.

Gathering data at the area of the lower heath land summit of Willstone Hill

Once data were gathered I joined them and we all set about pinpointing the critical col of Willstrone Hill, this proved to be ground beside a fence which thankfully was well sheltered from the strong wind.  Once the customary five minutes of data were gathered I packed the Trimble away and we walked up the good path to the summit of Hope Bowdler Hill.

Gathering data at the col of Willstone Hill

The high point of Hope Bowdler Hill is about 14 metres from its small summit cairn amongst heathland scrub of wind-blown grass.  Having been away from Trimbling hills for two months it was good to be out again, and especially so in the company of Mark and Bob, both of whom I hadn’t seen for quite a time. 

Gathering data at the summit area of Hope Bowdler Hill

After summit data were stored we retraced our inward route back toward the hill’s col and continued on another good path, this time amongst bracken toward the col of Helmeth Hill which was our last hill of the day.

The wooded summit of Helmeth Hill from the descent of Caer Caradoc

The col was positioned in a field and was Trimbled, however the summit is positioned in an attractive deciduous wood and although I set the Trimble up at the high point it did not achieve its accuracy level before data should be logged, and having waited five minutes for it to do so, we decided that I should switch the equipment off and it was time to head down.

Gathering data at the col area of Helmeth Hill

Our route toward Church Stretton took us steeply down through the wood and on to paths and tracks leading us to the periphery of the town.  Mark later checked the distance and ascent for the day’s walk and with approximately 600m of ascent it had proved a good day out, it was also good to see both Mark and Bob again, hopefully we’ll be on the hill again shortly.

LIDAR image of Hope Bowdler Hill (SO 479 940)

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:

Caer Caradoc (significant name change)

Summit Height:  459.5m (converted to OSGM15, from previous Trimble GeoXH 6000 survey)

Summit Grid Reference:  SO 47745 95390 (from previous Trimble GeoXH 6000 survey) 

Col Height:  185.3m (LIDAR)

Col Grid Reference:  SO 45734 93768 (LIDAR)

Drop:  274.2m (Trimble GeoXH 6000 summit and LIDAR col)

Dominance:  59.67% (Trimble GeoXH 6000 summit and LIDAR col)

Willstone Hill

Summit Height:  404.65m (converted to OSGM15)

Summit Grid Reference:  SO 48564 94370 (summit relocation)

Col Height:  382.2m (converted to OSGM15)

Col Grid Reference:  SO 48190 94230

Drop:  22.4m

Dominance:  5.54%

Hope Bowdler Hill

Summit Height:  425.5m (LIDAR)

Summit Grid Reference:  SO 47952 94040 & SO 47953 94042 & SO 47957 94045 (LIDAR)

Col Height:  306.0m (converted to OSGM15, Trimble GeoXH 6000)

Col Grid Reference:  SO 47961 94519 (Trimble GeoXH 6000)

Drop:  119.5m (LIDAR summit and Trimble GeoXH 6000 col)

Dominance:  28.09% (LIDAR summit and Trimble GeoXH 6000 col)

Helmeth Hill

Summit Height:  344.1m (LIDAR)

Summit Grid Reference:  SO 46948 93848 (LIDAR)

Col Height:  304.5m (LIDAR)

Col Grid Reference:  SO 47133 93753 (LIDAR)

Drop:  39.6m (LIDAR)

Dominance:  11.52% (LIDAR)

For details of the summit survey of Caer Caradoc

For details of the col survey of Caer Caradoc

For further details please consult the Trimble survey spreadsheet