OUCC Proceedings 1
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A Preliminary Report
No doubt some of the people who turned their heads to stare as we drove through Oxford at 6.30. pm. on Monday, July 31st, 1961, wondered for a moment or two about our possible doings in Spain during the next few weeks. Even the few people who gave us a send off from our base in Oxford, where they had seen some of our preparations, could not have known that we had been looking forward to and working for the next seven weeks for nearly a year.
Many months had been spent in getting the party of twelve together, and in enlisting support from societies and industrial firms; the generosity of the latter enabled the expedition to take place, and contributed greatly to its success. The last few days were a feverish whirl of checking and packing equipment and loading it onto our two ex-WD. Bedford lorries. Surprisingly we were only half an hour late leaving Oxford. After a night in London we drove on to Dover, crossed the Channel, and by 4.pm. were wondering why we had ever criticised British Roads.
It was as well that we were in no hurry to cross France, for though our vehicles ran well, we soon found that one of them wouldn't stop. Two long breaks for repairs were made, one overnight near Rouen, and one at Montignac, where we also saw the famous cave paintings of Lascaux and Les Eyzies. We didn't reach the Spanish frontier until late on Sunday evening; too late in fact, for the senior officials had gone home, and we had to spend the night in the no-mans land, between the frontiers.
As we drove along the north coast of Spain the weather broke, and by the time we reached Cangas de Onis, the town nearest to the scene of our operations, we were quite damp. We lost no time in presenting ourselves to the Mayor and to the barman, and having received permission from one and fortification from the other, we set off the next day for Covadonga, and the National Park of the Picos de Europas, where we were to camp. The road beyond Covadonga was very steep and very rough, and we were very grateful for the pulling power of our lorries. At about 2000ft. we passed into the clouds, and our search for a campsite near Lake Eņol wasn't particularly enthusiastic. But through the mist and rain appeared the dim outlines of a large stone-built house, and it turned out to be a Government-owned mountain refuge, similar to the Youth Hostels of this country, but without the meals service. We decided to stay there for one or two nights, whilst we dried out and established a camp-site; but the weather was so dismal and the position of the Refuge so ideal that we paid another visit to the Mayor of Cangas, and obtained permission to stay in the Refuge for as long as we wished, because we were students. So the "Estudiantes Ingleses" we became, and we were soon objects of great interest to the local populace.
On the Sunday the clouds began to lift and we were able at last to look at our surroundings. The Refuge was built on the side of a wide green valley, with the lake about three hundred to the left, and the deep gorge of the River Dobra about a mile to the right. Across the valley an extensive but thin wood of beech and oak rose up the hillside to about 4000ft.; beyond this was a rough expanse of gorse and bare rock, and beyond this again, about four miles away, the huge cliffs and precipices of the highest peaks towered above large patches of glistening white snow. We had established ourselves in the long verandah built onto the side of the Refuge, where we and out equipment were protected from the weather, and yet open to the air and the view. We were also within easy running distance of the lake, an excellent cooling-off place, for even at this altitude of 3700ft. the temperature was generally in the eighties, and quite often in the nineties. We were extremely lucky with the weather; according to the locals, we hit the best spell of weather within living memory. After the first three days we had hardly any rain at all. and as well as the gorse and bare rock, we had to contend with high temperatures when carrying out investigations above ground.
The area of mountains which had been chosen for examination is part of the Western Massif of the Picos de Europas, the highest part of the Cantabrian Mountains, which continue the line of the Pyrenees along the north coast of Spain. The Western Massif is bounded by two very deep gorges, that of the Dobra on the west, and the even deeper canyon of the Rio Cares to the east. The whole of the area is composed of limestone of Carboniferous age, rather similar to the Mountain limestone of this country, though much more highly folded. The highest peaks, Peņa Santa, 8517ft, and Santa Maria de Eņol, 8130ft, are part of an enormous wall, standing vertically above the surrounding slopes by as much as 1200ft. The area has been glaciated, and the bare rock surfaces, usually with well developed clints, contrast with the occasional green, moraine-filled valleys.
Of course, cave exploration was the major part of our programme, and there were plenty of them. Even during our first ascent of the mountain road. when we had stopped to give the vehicles a rest from their bottom gear grind, two cave entrances had been found; yet we never found the time to return to them. Altogether some sixty or seventy caves and potholes were investigated, and about thirty of these were surveyed, generally to C.R.G. Grade II. standard. To give a correct impression of the types of caves in the area. small ones as well as large ones were subjected to compass and tape.
The largest cave, named Pozo (pothole) Palomeru, after the hill on whose flank it lies, was the first one to be shown to us by the shepherds. The entrance was a vertical shaft, which we were told was fifty metres deep; a pretty good estimate, for we found that its depth was 142ft. This led to a system of generally large passages totalling four-fifths of a mile in length. At the bottom of the main shaft, another small pitch leads to a short upstream passage and to a junction; from this a long downstream (but not by any means all downhill) passage leads north-westwards for about a quarter of a mile. The other passage, from which an enormous volume of water must flow in times of flood, when the snow melts in early Spring, is smaller and shorter. ending in a large chamber and a series of avens. At the end of our stay an extension, with passages cut by pebble scour, was discovered just beyond the first lake.
A still more interesting system was first noticed quite early on during our stay, but as it was some distance from the base camp, it was only explored by chance. One very hot day, two of us were feeling thirsty, and thinking that any water found underground would be less likely to be contaminated, we entered this cave, with only one torch and a drinking mug; not the best equipped party for a first exploration. After a maze of entrance passages, with scallop marks showing water flow towards the entrance, a passage more than fifty feet high was reached, and our thirst was forgotten. The huge passage turned out to be only as long as it was high, but a climb into the roof at its end brought us to a large chamber, with several passages leading out of it. One of these led to another large passage, which in contrast to the rest of the cave was perfectly straight. At this point common sense prevailed at last. and we made for the surface. We didn't find any running water underground, even though we were in the cave for more than two hours, and we had to be content with a drink from the surface. Later a more detailed exploration was made, and this time the party was better equipped. The straight passage we had seen turned out to be a fissure running straight for twelve hundred feet; as much of it involved a tricky traverse along the upper part of the passage, the trip was quite arduous, but well worth while on account of the wonderful formations in the fissure. At the inner end the passage sloped down to a stream, rising from a pool and sinking into the lower part of the fissure; the cave so far described seems to be merely a flood outlet for this stream. The passages found total nearly half a mile.
The third large system investigated was near the village of Covadonga, where a large stream disappeared into the Cueva Orandi, and reappeared at the shrine of Santa Cueva. some seven hundred feet lower. Two trips were made, and about three hundred feet of this depth were surveyed; the deep lakes at the foot of two of the ladder pitches added greatly to the fun.
Many other smaller caves were investigated, and these were of varying types. In the area of the Vega de Comeya, a flat-floored solution valley (polje) two miles in length, there were two groups of caves near the cliffs on the south side; those near the edge of the cliffs, which showed chiefly vertical development, though they did not extend as far as the valley floor; and those in the face of the cliffs, about two hundred feet above the valley floor, which were short and showed horizontal development. There was also a group of small caves in an outcrop in the middle of the valley, probably the various outflows of the same stream at different times.
On a broad time scale, the caves appear to be of two ages; most of the small caves are very old, often with large deposits of soft stalagmite, apparently the result of stalagmite decay. The larger systems are more recent, and both Pozo Palomeru and Cueva Orandi are still in process of active formation.
One of the highlights of the expedition was a five-day camp in the mountains, the objects being to look for caves (of course), to have a look at the effect of altitude on the weathering of limestone, and generally to enjoy the scenery. We camped at a spring at about 6300ft, on one of the few patches of grass in an area of great expanses of bare rock and scree. There were hundreds of holes of every description; fissures, shafts, caves, the lot; so many in fact that we gave over even counting them, and turned to mountain-climbing instead. The Gran Hoyo de los Pozos (Great Valley of the Potholes) was only one of several large enclosed valleys; these were probably excavated to their present shape by the glaciers which occupied these mountains during the Quaternary Period of glaciation, since when they have been sculpted in detail by the processes of solution. Any former corrie lakes have been drained by the pothole systems which have developed at the lowest points of the valleys. Many of the potholes had become blocked by boulders, the product of frost-shattering, but others are open, and this upper area has an enormous potential for new discovery. One cave of special interest was the cave of the Snow, so called because its main chamber, one hundred feet across, contained about fifty years' accumulation of snow, to a depth of thirty feet.
Other work carried out by the Expedition included a record of the flow temperature, and pH. value of two springs; water tracing (though in this we were hindered by the acute drought); geophysical surveys, using a resistivity meter and aimed at checking the position of underground cavities; meteorological observations adapted to record the conditions of weather at the rock surface, ie., the conditions which affect erosion; and examination of the forms of the rock surface.
Meanwhile, four members of the Expedition were busy in Galicia, investigating the rock carvings there. As many different types of carving as possible were drawn to scale using a standardised technique, and many were photographed. Here temperatures were even higher than those in the mountains, and it was impossible to work in the middle of the day; luckily many of the sites were close to the excellent beaches of this part of Spain.
All too soon it was time to think about getting back to England. The archaeologists returned to the base camp, and together we de-laddered the caves and packed our equipment. On the morning of September 14th. we left the Refuge, but we had gone only three miles down the mountain road when the breaks began to give trouble again. After a repair session we did manage about fifty miles that day, but most of the night, for the drivers anyway, was spent once again in checking the brake system. After this we idled our way across Spain, enjoying the low cost of living, and then crossed France in forty-three hours, which allowed us a very necessary day in Boulogne for yet more repairs. The hot weather continued; 99F. in mid-France in late September -- but when we reached Boulogne the clouds were gathering, and England was shrouded in mist. We were home! On Thursday, September 21st, we recrossed the Channel and drove back to Oxford.
Perhaps the best proof of our enjoyment is that we all want to go back. But whether we do or not, the Picos de Europa, and this expedition to them, will always be among our brightest memories.
It is hoped to publish a detailed report under the auspices of the Cave Research Group*. It is also expected that there will be more O.U. Cave Club forays to this area, and that their work will be published in future numbers of these Proceedings.
[* Report was published as "Oxford University Expedition to North Spain", CRG publication 14, November 1965.]