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SWCC CANTABRIA 1998 EXPEDITION
The SWCC returned in the summer of 1998 to the site of last year's expedition
in the Cantabrian mountain range in Northern Spain.
Here are some pictures from Martin Hoff and Brian Clipstone, followed by an
interim report on the expedition.
Photos by Martin Hoff
Photos by Brian Clipstone
 
EXPEDITION INTERIM REPORT
In August 1998, twelve members of the South Wales Caving Club spent two weeks
in Ramales de la Victoria, Cantabria, northern Spain, to continue with cave exploration
on the nearby area around Pico San Vicente. This project had been started on an
expedition by the same club in summer 1997, and further work had been done by
a small team at Easter 1998. This report will provide an outline of the work done
by the 1998 expedition; a fuller report will appear in a forthcoming edition of
the South Wales Caving Club's Newsletter.
Background
Before summer 1997, there was very little known cave of any significance on Pico
San Vicente, despite its obvious potential and the presence of major cave systems
under neighbouring hills. Following an initial reconnaissance and contact with
the local caving club, Agrupacion Espeleologica Ramaliega, an SWCC expedition
in July/August 1997 divided the hill into nine areas and began systematically
searching each one for likely caves, using GPS (Global Positioning System) sets
to record the position of each promising site. The establishment of a GPS base
station at the campsite enabled a "differential GPS" system to be used, which
significantly reduces the degree of error inherent in GPS data (caused by the
deliberate scrambling of the information sent by satellites by the US authorities).
Much of the terrain on the hill is rugged karst landscape, progress over it
is slow and for this reason most of the work was concentrated in area "A", which
was felt to have good potential. (Area A forms part of the Pena de Rozas, and
includes the Pico de Hoyufresno, the highest point on the main ridge.) A total
of 42 sites of speleological interest were logged, some of these were descended
and showed that finding significant cave passage on San Vicente was a real possibility.
A small team from SWCC visited the area again at Easter 1998 for one week,
and although activities were hampered by poor weather they managed to descend
some of the sites previously noted as well as walking on Hornijo and undertaking
some sporting caving.
The August 1998 Expedition
The expedition took place from 31st July to 14th August 1998, and we were fortunate
enough to be allowed to camp again at the public park Gandasson-Cubillas in Ramales
de la Victoria. The South Wales Caving Club would like to place on record its
thanks to Ayuntamiento de Ramales de la Victoria, and to the town's mayor, for
their kindness in allowing us to use this site again. We would also like to thank
Mr. Rafael Zorilla of nearby Riba, for his continued help, both with local liaison
and for storing some of the team's equipment, and the Agrupacion Espeleologica
Ramaliega for their continued support.
A GPS base antenna was again established at the campsite, which has proved
an invaluable asset to the exploratory work. A generator provided power for
a computer to be run on-site, which allowed GPS data to be downloaded immediately
and surveys to be plotted.
Objectives
The 1998 expedition set out with the following objectives:
- to continue descending previously recorded sites of interest in San Vicente
area "A", surveying each one as it was descended.
- to finish the surface sweep of area "A", recording sites with GPS as before.
- to continue the sweep of remaining areas of San Vicente.
- to search for possible resurgences in the river valleys to the north and
east of San Vicente - the Ason and Gandara respectively - taking water temperature
readings to try and establish the precise locations at which cave water from
the mountain appears in the rivers.
These objectives will now be dealt with in turn.
- to continue descending previously recorded sites of interest in San
Vicente area "A", surveying each one as it was descended.
This objective occupied most of the manpower for most of the time, due
largely to the fact that some significant cave systems were discovered,
some of which took several days to rig, explore and survey.
Members of the expedition tackled this work in groups of two or three,
and soon realised that finding previously-recorded sites was seldom straightforward
despite the red paint used to mark all the sites. The original plan - to
work through the sites in numerical order - was soon abandoned in favour
of descending sites as and when they were located, then comparing notes
with other teams and returning to "tick off" any remaining sites at a later
date. A spell of hot, sunny weather further complicated matters as although
this meant that visibility was good, it made carrying ropes and equipment
across the tough terrain hard work.
While all of the sites previously found had been logged using the GPS
equipment, in many cases the set had only been "on station" for a few minutes
and for this reason most sites were re-logged to provide much greater accuracy.
In some cases, the GPS sets were on station for several hours while the
deeper shafts were explored.
Bosch 24-volt cordless drills were used to facilitate the placing of bolts
for descent, and all teams agreed that this approach was worthwhile, both
in terms of time and effort saved and increased safety. Also, so-called
"stud anchors" were used in place of the more usual "spits". These have
several advantages; the hole can be drilled to any depth (as long as it
exceeds the minimum necessary), does not need finishing "by hand" with a
bolt driver, and after use the outstanding bolt can be hammered back flush
with the rock face, leaving little visual evidence of the caver's presence.
While this renders the bolt useless for further trips this is of no consequence
in shafts that don't "go".
The team's most significant finds were as follows:
SVA 30 Surveyed depth: 191m
This surface shaft in the upper amphitheatre was pushed by a team of three
over several days. The immediate area around the red paint-marked "SVA 30"
is peppered with shafts and after dropping stones down several of these the
team opted for the one that sounded deepest. Initial exploration, in what
was later named the "P.O.W. Series", indicated that the shaft bottomed out
at around -65m but the team then found an alternative route which was pushed
for several pitches to a slot at -80m, down which a good draught was blowing.
The walls of some of these pitches were covered in a moonmilk-like substance,
with which rope and equipment soon became caked, making exploration arduous.
Beyond the slot, the passage became a huge rift which descended more or
less vertically to the final limit at -191m. However, no evidence was noted
of the draught at this point and the two members of the team who took part
in the final push could not establish where it goes. This does leave something
of a question mark over this part of the cave but the two cavers concerned
searched the shaft extensively and could find no evidence of any other way
on. However, one or two other possibilities remain to be investigated in
the area around the slot, draughts enter the cave higher up and given the
results in this cave the other surface shafts in the same immediate area
deserve further, more thorough investigation.
SVA 34 Surveyed depth: 126m
Another shaft in the upper amphitheatre, this site had been considered one
of the most exciting found during the surface sweep in 1997 due to the great
distance down which dropped stones could be heard to fall. It was descended
at the end of the 1997 trip and a blockage reached at around -50m. A team
of three revisited the site on this year's trip and removed the blockage with
a crowbar, encouraged by the presence of a cold draught. They continued exploring
over several days, surveying as they went and eventually reached an impenetrable
slot at -126m. It is worth noting that the slippery mud which made exploration
difficult in SVA 30 was also present here. Two potential parallel shafts were
later examined but both ended in tiny slots. This cave also had a good draught
evident which could mean it is connected to a much larger system but the team
concerned consider it unlikely that any further progress will be made at this
site.
SVA 16 Surveyed depth: 90m
This is a big, obvious surface shaft on the NE rim of the upper amphitheatre
which was descended on the first full day of the expedition. A descent of
20m was made to the gravel floor visible from the surface, from the far end
of which a window up one wall was seen. (As an aside, it is worth pointing
out that this window was not visible even the other end of the floor or from
any point higher up, which indicates the need for thorough investigation of
every site!) A slippery 3m climb gave access to this, from where dropped stones
could be heard rattling for some distance, much to the excitement of those
at the surface. The rope was rigged some 8m to a tight slot, from where a
20m near-vertical hang landed on a big gravel ledge above a wide, deep rift.
At this point a halt was called, due to running out of rope, and a return
made next day.
Two cavers pushed the shaft while two others followed, surveying. The
rift descended almost vertically for more than 40m to a gravel floor from
which there was no way on. On the ascent some time and effort was spent
investigating the possibility of a parallel shaft, to which it was considered
access might be available from a large ledge of boulders. This proved inconclusive:
while the caver stationed at the gravel floor thought that one or two of
the stones dropped from above seemed to echo from "behind" the back wall,
most landed at his feet.
The tight slot below the "window" proved challenging for both descent
and subsequent ascent, and cost one member of the team a carbide generator
as he struggled to get back through it!
SVA 33 Approximate surveyed depth: 50m
Another shaft in the upper amphitheatre, this was initially descended for
some 30m to a gravel floor. (The presence of a "spit", beside a ledge some
8m from the lip of the shaft, indicated that someone had previously examined
this site.) Having ascertained that there was no way on from the bottom, a
side route was examined which was found to connect to another nearby daylight
shaft and this was bottomed at -50m. Despite the impressive scale of this
shaft, no way on could be found.
SVA 23 Approximate surveyed depth: 46m
The most promising of the sites in the lower amphitheatre, this at first seemed
to offer good potential but was found to end at -46m.
SVA 29 Approximate surveyed depth: 40m
This site in the lower amphitheatre was descended right at the end of the
1997 expedition, when a mud floor at -11m was reached from where a slot led
into a long rift, down which stones echoed encouragingly. A lack of time and
rope forced a withdrawal at this point but the two cavers concerned revisited
the site on the first day of the 1998 expedition, descending the rift to a
depth of -40m where a gravel floor offered no way on. Some time was spent
on the ascent investigating a possible parallel shaft beyond a window but
this proved to be just a short sloping rift that closed down.
It is hoped that fuller descriptions of all of the caves explored, along
with surveys and photographs will be published in the forthcoming SWCC Newsletter.
- to finish the surface sweep of area "A", recording sites with GPS as
before.
With most of the team occupied in descending and surveying shafts, nothing
was done in pursuance of this objective until the last full day of the expedition,
when a team of seven took two GPS sets onto the hill. A total of twenty-five
sites were recorded and logged using the GPS; some of these sites consisted
of several promising shafts in close proximity to each other and these were
generally given a single "SVA" number. The area swept was that to the east
of the two amphitheatres previously examined. It forms the eastern flank
of the Hoyufresno massif, and includes the pass between this massif and
the Muesca Chica to the east. Two large dolines were investigated (one of
which forms, or is located within, the pass) both of which contained several
very promising sites. Traversing the terrain here was considerably more
difficult than that previously encountered, and for this reason while the
upper doline was comprehensively surveyed, shortage of time meant that the
lower was only cursorily examined and the eastern half of it hardly at all.
It may be that some sites were missed as walking with the team in a line
was impossible. Those present on the hill that day had no reference material
to define the extent of Area A so it may be that we did not cover all of
the terrain originally designated as Area A. All of those who took part
in this exercise were convinced that the area covered offers great potential
for finding cave and warrants further work.
- to sweep remaining areas of San Vicente.
Little was done on this objective, although some sites previously recorded
in area SVE were explored on the last day of the expedition. The sites noted
in this area proved to be generally immature cave features, usually thin
rifts which would require serious digging to produce any meaningful progress.
One was found to consist of exceptionally rotten rock, several contained
various animal skeletons (including a horse's skull!) but the final one
dropped (SVE 3) was the best of the bunch. Some further progress may be
expected at this site, but it is wet, muddy, very slippery and loose in
places. It does, though, display some nice "flowmud". A hammer would be
needed.
- to search for possible resurgences in the river valleys to the north
and east of San Vicente, taking water temperature readings to try and establish
the precise locations at which cave water from the mountain appears in the
rivers.
No work was done on this objective, although various members of the expedition
made brief reconnaissances of the area previously identified as lying close
to an underwater resurgence beside the Rio Gandara, where the AER are currently
engaged in digging activities. Of the two rivers, the Gandara and Ason,
the former seems most promising on the basis of current information.
Other Activities
Eight members of the expedition, including the two geologists present, took part
in a walk from La Gandara to Riba, via the huge doline (1km across) of Hoyo Masallo.
While a day's walk was only able to cover a small proportion of the Hornijo massif,
the area has clear potential as evidenced by the numerous shakeholes adjacent
to the path. (The team were also impressed at finding a hole emitting a cold draught,
near Hoyo Salzoso, just yards from the main path!)
The verdict of the geologists was that the areas of the mountain which consist
of "reef" limestones were those most likely to repay serious investigation.
It is clear that careful scrutiny of any area of Hornijo, and its subsequent
speleological exploration, will occupy a great deal of time and manpower.
As well as the exploratory work, some managed to find time for other caving
activities. Several "tourist" trips visited Cueva Coventosa, and those seeing
it for the first time were impressed with the scale and sporting nature of the
cave. Sadly, a rope placed on the vertical drop close to the cave entrance was
removed by persons unknown some time between 2nd August and 12th August.
Three trips were made to Cueva Ca�uela, with one party using large M22B flashbulbs
to take photographs in the large entrance passage. However, the large passage
at the end of the cave is not as easy to locate as the survey in Grandes Travesias
would suggest and none of this summer's trips managed to find it.
Conclusions
Our initial investigations in 1997 led us to believe that significant cave passage
exists under Pico San Vicente. This year's expedition has proved that belief to
be justified, with several deep caves found along with evidence of good draughts,
which would seem to indicate the presence of major cave passage beyond present
limits. Of the terrain scrutinised so far, the upper amphitheatre in Area A would
seem to offer the best hope of gaining access to a major cave system. In particular
the site labelled SVA 30 and its associated shafts may warrant further investigation.
In the light of this year's discoveries, the remainder of Area A needs to
be explored with the same methodical approach and thoroughness used so far,
as do the other areas of San Vicente. This work will no doubt occupy members
of future expeditions for considerable lengths of time.
The GPS equipment had already proved its usefulness in 1997 and this was underlined
by the 1998 expedition. It is hoped that an accurate map of all the sites recorded
will be available soon.
The use of Bosch drills and stud anchors proved to be an extremely fast and
safe means of descending previously unexplored shafts and we would wholeheartedly
recommend that future expeditions adopt this approach.
Future Work
At the time of writing it is envisaged that SWCC members will make two visits
to the area in 1999; a small team are planning a week's trip for Easter, while
a (hopefully) larger group will travel out in the summer.
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