29.09.20 Hafod Ithel (SN 610 677)
I’d wanted to visit this
hill for many years but until today had never done so. Although, in part, I wanted to visit its
summit, after all this would be another P30 bagged and surveyed, it was its
connecting bwlch that was the real interest for me.
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| The summit of Hafod Ithel (SN 610 677) |
Hafod Ithel is the
highest hill in the area of land to the west of the Elenydd and north of Mynydd
Preseli and the hills of Pembrokeshire.
Its connecting bwlch is to its east and could be one of two points with
a land mass between which has the summit of Banc y Maen Rochorlem (SN 675 691)
as the highest. This latter hill was
also on the day’s surveying agenda, but that could wait until after visiting
the summit and bwlch of Hafod Ithel.
For many years the only
source available for hill list compilers who wanted to document the drop of
Hafod Ithel were Ordnance Survey maps of the day. These are the 1:50,000 Landranger and
1:25,000 Explorer maps. Both scales of
mapping have contours between 200m – 210m for the two bwlch options for Hafod
Ithel, with the 1:25,000 Explorer map giving a 202m spot height positioned at
SN 64839 68745 beside a stream and probably not at the critical point for the
westerly bwlch option, and a 204m spot height at SN 69535 68656 positioned on a
road and in all likelihood not at the critical point for the easterly bwlch
option.
The land mass that takes
in Banc y Maen Rochorlem connects with land to its immediate north which then
extends westward to the sea and also extends northward toward and following the
Afon Ystwyth. Therefore, the area taking
in this land mass has a number of qualifying P30s that could, in effect, have
either Hafod Ithel or Carn yr Hyrddod (SN 790 704) as their parent hill.
Since the days of hill
list compilation using just paper maps, there has been a welcome revolution. This takes in independent surveyors, online
mapping and LIDAR. The latter does not
at the moment cover the whole of Wales, however it does cover the easterly of
these two bwlch options and I LIDARed this a number of months ago, the result
came to 206.210m at SN 69578 68344.
Therefore, the westerly option for the bwlch now required surveying with
the Trimble GeoXH 6000.
Even though the summit
of Hafod Ithel and Banc y Maen Rochorlem are covered by LIDAR, I still wanted
to survey each with the Trimble and the first on my surveying agenda was Hafod
Ithel.
The ascent of this hill
can be an easy one and with a number of hills planned to visit during the day,
this was my preferred option. I parked
beside the narrow road that winds its way over the western flank of the hill
and followed a greened vehicle track on the moor to the summit.
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The memorial to the Four Poets overlooking my parking place
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The summit of Hafod
Ithel is crowned by a triangulation pillar and within a few minutes of arriving
on top I’d positioned the Trimble aligned with the high point of the hill and
waited for the allotted data to be gathered and stored.
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Gathering data at the summit of Hafod Ithel
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During data collection I
wandered below the high point looking back at the wind turbines near the summit
of Hafod Llŷn (SN 625 700), a summit I had just visited and
surveyed. Away to the south grey bulbous
cloud hugged near the tops of the Preseli hills, whilst below the watered
depths of Llyn Eiddwen glistened.
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Llyn Eiddwen
|
Once I closed the
equipment down and packed it away, it was only a short distance back down the
greened track to the car. Before leaving
I visited the memorial stone to the Four Poet’s which sits proudly beside a rib
of rock.
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The memorial to the Four Poets
|
I now navigated the
narrow lanes to and beyond the small community of Bronant and parked on a grass
verge close to the farm of Pwllpridd.
From here I walked back up the lane to a track that headed down toward
the area of the bwlch. The grey cloud
that had hugged the Preseli tops had pushed northward and the forecast continuing
sun for the day was now partly obliterated.
The track wound its way
down to an avenue of trees and grazing fields.
Beyond was a mass of reed grass leading to a small conifer
plantation. The reed grass indicated bog
and this looked extensive. However, this
route in to the area of the bwlch took me down toward it and bi-passed what
looked like horrendous underfoot conditions.
Arriving at the bwlch I
first investigated the area of extensive reed grass and stepped over a drainage
ditch come steam to get there. Prior to
visiting I’d looked at the 5m contouring that used to be available on the OS
maps website and used this as an indicator for where the critical point lay as
the 205m contours almost joined and the ten figure grid reference I had noted
indicated the critical point to be back the way I had come.
Striding back over the
murky stream come drainage ditch I zeroed in to the point where the OS Maps 5m
contouring gives as the bwlch. This was
close to a gate and a muddied land bridge that crossed a wide drainage
ditch.
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The bwlch of Hafod Ithel
|
I took two data sets,
one from where the 5m contouring indicated the critical bwlch was positioned
and the next on the same valley to valley fence line and an equal distance on
the opposing side of the gate.
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Gathering data at the first of two surveys at the bwlch of Hafod Ithel
|
During data collection I
stood back away from the reed grass and assessed the lay of land at it came
from the small conifer plantation toward the gate. I judged land a few metres from either side
of the gate descended north-westward and from its east descended toward the
extensive reed grass beside the conifer plantation.
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Gathering data at the second of two surveys at the bwlch of Hafod Ithel
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As the Trimble beeped
away I sat on the lower part of the gate and waited for the allotted data to be
gathered and stored. This bwlch must
only be frequented by an occasional passing farmer and if not for the wide
drainage ditch it would no doubt be a quagmired bog.
Happy with the two
Trimble placements that can be compared for the height on the valley to valley
traverse I packed the equipment away and retraced my inward route back to the
car.
Survey Result:
Hafod Ithel
Summit Height: 360.4m (converted to OSGM15)
Summit Grid Reference: SN 61062 67794
Bwlch Height: 204.4m (converted to OSGM15)
Bwlch Grid Reference: SN 64577 68898
Drop: 156.0m
Dominance: 43.29%
For details on the 2nd
visit to Hafod Ithel
For further details please consult the Trimble Survey Spreadsheet
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