15.02.18 Worcestershire Beacon (SO 768 452, only col Trimbled)
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| LIDAR col image of Worcestershire Beacon (summit at SO 768 452) |
There’s a pleasure surveying a col that isn’t positioned in what could generally be referred to as the uplands, and especially so if the col is situated away from urban development. The cols I have surveyed that meet this description are usually quiet places, seldom visited except by an occasional farmer. They are places that a walker would rarely go, and as for a hill bagger, well, there would be little reason to visit, except of course if wanting to increase the accuracy of numerical data in a hill list, and to do so via a survey.
Today’s such col is situated
about a mile west of the busy A 49 road and to the south of Ludlow and between
the small communities of Ashton and Orleton.
The col is the critical one for Worcestershire Beacon, a hill whose
summit I surveyed in early October 2015; this hill is listed as a Marilyn, Hump
and a Four. Its summit is probably one
of the most visited of any hill in Britain, and yet its col is a forgotten and
quiet spot positioned on an earthen vehicle track or close by in an adjacent
field, I surveyed both.
Leaving Worcester at
just past 10.00am I had a good day ahead with a number of walks and hills planned
to visit and survey before a 6.00pm rendezvous in Newtown with friends for a
meal and the cinema, I wondered if everything I planned to survey could be
accomplished.
By 11.20pm I had my
wellies on and was walking down the earthen vehicle track having parked my car
at the junction between it and the narrow lane leading to Orleton.
Map contours suggest
that the col of Worcestershire Beacon is placed in the adjacent field to this
track on its eastern side, I’d come prepared with two sets of ten figure grid
references, one on the track and the other in the field where interpolation
suggests the col to be placed.
As with many col’s it is
the valley to valley direction that is the hardest to visually determine, and
as I walked past where the col is situated to the point where the hill to hill
traverse descends from the south I followed this traverse back on the track to
where I judged its low point to lie, during this time I had the Trimble
switched on to log in to satellite reception, when I determined my chosen spot
for Trimble placement I checked the ten figure grid reference I had noted for
where interpolation suggests the col could be placed on the track , and my
chosen spot was within a couple of metres.
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| Gathering data at the first Trimble set-up position at the col of Worcestershire Beacon (looking south) |
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| Gathering data at the first Trimble set-up position at the col of Worcestershire Beacon (looking north) |
Once the Trimble was set
up I waited about ten minutes for it to achieve its 0.1m accuracy level before
data should be logged and then waited another five minutes for the allotted
data points to be gathered. During this
time all was thankfully quiet on the track, although tyre marks from a tractor
were evident in the mud either side of the thin strip of grass in the centre of
the track, indicating that the local farmer had come this way recently.
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| Gathering data at the second Trimble set-up position at the col of Worcestershire Beacon |
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| The second Trimble set-up position at the col of Worcestershire Beacon |
After gathering up the
Trimble I walked back down the track to where a gap in the adjacent hedge gave
access to the field on the track’s eastern side, this field was extensive and
so I followed the hedge to where it bisects with the point at which the Trimble
had been set-up on the track and checked this position against the ten figure
grid reference noted for the field, I then wandered around a bit and moved the
position of the Trimble a few metres before setting it to gather data.
As the Trimble gathered
data I stood beside the hedge and hoped that I would blend in as I was in view
from a house across the field, but again all remained quiet. Once I packed the Trimble away I exited the
field through the gap in the hedge and wandered back down the track to my car,
next stop Wapley Hill.
Postscript:
Since the survey of this hill full LIDAR coverage is now 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 this hill has been analysed using this technique, resulting in the LIDAR height and position for the col of this hill prioritised over that produced by the Trimble GeoXH 6000.
Survey Result:
Worcestershire Beacon
Summit Height: 425.4m (converted to OSGM15, from previous Trimble GeoXH 6000 survey)
Summit Grid Reference: SO 76882 45230 (from previous Trimble GeoXH 6000 survey)
Col Height: 85.2m (LIDAR)
Col Grid Reference: SO 50203 66471 (LIDAR)
Drop: 340.2m (Trimble GeoXH 6000 summit and LIDAR col)
Dominance: 79.97%
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