UKHillwalking Article
UKHillwalking recently published an article on the survey of Bache Hill, which was one of the most important hills remaining to survey in Wales.
Bache Hill - A Mountain Mystery Finally
Solved
Located
in the Radnor Forest in the Mid Wales borderlands, Bache Hill has long been
subject to doubt as to its status as a mountain. On OS maps its 610m high point
is very close to the agreed mountain height threshold of 2000ft (609.6m), but
the trig point stands on an ancient burial mound. Did this man-made structure
give Bache Hill an undeserved boost over the line? Hill surveyors Aled Williams
and Myrddyn Phillips thought it was high time to settle the question.
Bache Hill is rather unassuming, positioned close to border country in eastern mid Wales with a large conifer plantation to its north and reclaimed grazing land to its south. The hill's one redeeming feature is its impressive summit tumulus, which at 3m in height and 20 metres in diameter is one of the finest of its kind in this part of Wales. This was built in the Bronze Age approximately 5,000 years ago and stands aloof overlooking this hill's heathery summit plateau. But is it the hill's true high point?
The ancient tumulus cast doubt on Bache Hill's 2000ft status |
Therefore, the base of the tumulus is about 607m in height; in relative terms this is quite a bit lower than the 609.6m (2,000ft) benchmark height required for Hewitt (2,000ft P30) and Nuttall (2,000ft P15) status. Although impressive it's been thought that the tumulus could be this hill's downfall, as it is man-made, and some hill list authors and hill baggers discount such a construct from being included as a part of the hill's height - and especially so if the natural summit is intact and not buried under the tumulus.
However, I'd visited this hill on 21 previous occasions and although not having stood on its summit for 16 years, I remembered looking west from the top of the tumulus to a bed of heather and wondering if in fact the natural summit of the hill still existed, since the ground thereabouts looked as if it might be higher.
Was the natural summit of this hill in fact to the west of the questionable tumulus, and if so was it sufficiently high to break through the 2,000ft (609.6m) barrier?
It's unassuming, but is it a mountain? |
These ramifications had all
sorts of potential conclusions: the natural summit may be under the
tumulus; it could still exist; if so where was it; was it above
or less than 2,000ft in height; could it even be higher than the top of
the tumulus?
Bache Hill might no longer
be accepted in the Hewitt or Nuttall listings if the natural summit was below
2,000ft, or conversely it might remain even if the natural summit existed
and was below this height, as long as the tumulus was over 2,000ft
(609.6m). It was all rather mind boggling, especially when there are those
that would discount the height of the tumulus in preference to the natural
summit if the latter was proven to exist, even if lower than the tumulus.
So many
questions to answer and only one way to find out; survey the hill.
- We gathered
four data sets from the base of the tumulus, each 90° from one
another. This would give a good spread of height and indicate where
the higher and lower ground met the tumulus.
- One data set
was gathered from the high point of the tumulus which is about one metre
from the base of the trig pillar.
- A further data
set was gathered just to the north-west of the tumulus on rising ground.
- And a further two data sets were gathered westward of the tumulus about 100 metres from it. It was here that we considered the natural summit of the hill to be positioned.
The 8th survey, in the vicinity of the natural summit |
And what of the results? Take a deep breath…
Base of tumulus:
- 1st survey: 607.869m
at SO 21377 63648
- 2nd survey: 607.608m
at SO 21392 63653
- 3rd survey: 607.024m
at SO 21397 63642
- 4th survey: 607.278m
at SO 21382 63635
Although the base of the
tumulus undulates, the position of the first survey indicates ground on its
western side is the highest and ground on its eastern side the lowest. This
confirms what we thought when standing beside the trig pillar as ground to our
east gradually descended, whereas ground to our west definitely went uphill.
Top of tumulus:
- 5th survey: 610.121m
at SO 21386 63643
To the north-west of
Tumulus:
- 6th survey: 608.416m
at SO 21353 63662
100 metres to west of
Tumulus:
- 7th survey: 610.094m
at SO 21281 63610
- 8th survey: 609.904m
at SO 21271 63605
Conclusion:
The 7th and
8th surveys complement each other and confirm the natural summit of this
hill is intact and is at, or in the vicinity of, grid reference SO 21281 63610.
The measurement offset for
the 7th and 8th surveys was taken down to the base of the heather in
the peat. However, you could easily go down a few more centimetres if so
inclined, but you would have to go down a further 0.487m (about 1½ft) for this
part of the hill to be below 609.6m. This confirms the natural summit is
over 2,000ft (609.6m) in height.
Lastly, the Trimble result
gives the 7th survey as only 0.027m below the high point of the
tumulus. That a natural summit exists, and its position west of the
tumulus was not a surprise, but its height being so close to that of the
tumulus was.
Bache Hill can again rest in
the knowledge that it retains its 2,000ft status, both to its ancient tumulus
and now also confirmed to its natural summit.
For the original article published on the UKHillwalking website
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