Matienzo 1986 The secret discoveries of Simon Chandler, aged 11½

When joining an overseas expedition there is the hope that new passage or even new systems will be found. There is the further hope that you will be the one that explores it first. In 1986 Simon and I fulfilled those hopes, with Simon's having the greatest significance

Expeditions to the Matienzo valley and the surrounding hills and three connecting valleys in northern Spain have been held annually since 1969, with the most serious and fruitful exploration occuring during the last twelve years. The full description of previous expeditions can be found in 'Caves and Caving' over the years and in a BCRA Transactions. This year's expedition attracted cavers mainly from the north of England. The Bradford Pothole Club brought assorted children, camp kitchens, canvas chairs, a caravan and wives looking for the pony trekking centre and supermarket. People arrived by car, taxi, Land Rover, camper van, bus, bicycle and on foot. Some had to depart on foot as well because their car was written off after trying to bend four French trees. People came and went; probably fifty in total, with the maximum of around thirty camping in the trees in the village. One girl, who had come by bus from West Germany, on her first trip underground was forced to sit alone for six hours whilst we photographed. Unfortunately she was not fit enough for the trip. A Bradford lad, 200 meters into his first trip underground in the same cave fell and badly damaged his knee, which required hospital treatment. In all three people had to visit the hospital, the other two sustaining their injuries above ground: playing football against the locals in an international match (British Cavers 4, Spanish Villagers 9); the other, attempting to separate a fight, suffered a cracked collar bone. The footballer's knee injury required a cast and he had to return home.

The summer's activities were rewarded with the connection of caves from valley to valley. Now three valleys are joined into one system, making it the third longest in Spain at approximately 32 km. The search is on for the route into the fourth, and last, valley of the area. One major connection made the front page of the regional daily newspaper and was followed up with a feature article on the expedition. Our personal contributions were for me to extend a cave into an old high level fossil series by walking into it from the end of a known cave, and for Simon to be in a group which squirmed their way through mud and squeezes into 3 km of large passages, one of which popped up in the floor of a cave only previously accessible by free diving a 7 m long sump. This connecting series of passages was called the 'Boy's entrance' after Simon. The story of this exploration typifies much cave discovery, a mixture of hard work, disappointing effort and relatively easy final break through.

The main sink, Cacaveuso, for the Matienzo valley is at its northern end about 600 m from the camp site. Each year an entrance has to be cleared of trees, branches, plastic bottles and carcasses to gain entry into breakdown passage which soon joins with the river, now underground. This quickly runs into a lake having a boulder strewn sump; in all 250 m of passage. The sink has been known since the very early expeditions. Another cave, Llueva, was discovered in an adjacent valley in 1974 and nicknamed El Biggo as the average passage size could accommodate two lanes of double decker buses. Exploration in this cave was restricted by the need to swim canals and dive a sump, this being free divable only in the last two years. It was always thought that Cacaveuso and Llueva were dry connected as they were relatively close and the sink had a strong draught blowing out. This draught obviously could not come from the sump but came from within a breakdown chamber above and to one side. Smoke bombs had been fired in Llueva at predetermined times to see if the smoke entered the sink cave. As there were known blocked, but draughting holes, on the hills above the surface was also monitered. This year two bombs were let off on separate occasions; the smoke being quickly sucked away in Llueva never to be seen again above or below ground. This was disheartening as it was felt this was the best way of verifying a connection. In the breakdown chamber in Cacaveuso the search for the draught had reached heights and crevices with no result. Ladders were also left rigged from year to year in the hope that the moving air would be found in this muddy filthy hole. But a great deal of energy, manhours and deodorant had given a negative result.

It was the middle of an afternoon, about three o'clock, when four people, Jim, Bill, Terry and Jane walked past our tent. I had not been well and was resting; Simon was lounging looking bored so they invited him for a short poke around in Cacaveuso. At nine o'clock Simon and Jim walked past the bar (where I was recuperating) to wash their gear in the river, saying to all around that nothing had been found. I walked to the river with them. Simon was obviously suppressing some excitement and nervously asked Jim, "Can I tell him?", "Alright" replied Jim. They did not want to shout about their discoveries but to enter it in the expedition log book and wait for reactions, but I got the story from a bubbling and ecstatic Jim, Bill, Terry and Jane. They went into the breakdown chamber and where the others had gone up to search for the draught they went down. A series of short drops between boulders, crawling through mud, pushing two squeezes lead to a short passage ending in a rift. A climb up entered a classic phreatic passage which disappeared into the straight line distance. They walked on, ignoring open side passages to reach a large chamber. The obvious way on was ignored to pursue a straight line. This was not pushed to its end. In this initial exploration they had found 1 km of passage.

The reactions of the other expedition members ranged from total disbelief to the view that the length of passage had been grossly exagerated. Juan Corrin, the leader, was eventually convinced of the discoveries, but initially he did not believe an eleven year old boy's story of large and long passages. The next day a party of twelve gathered with surveying equipment to test the validity of the claims. When into the new passages it was hard to restrain them from disappearing in all directions. Order was found in splitting into three groups of four people, each group taking a major passage and surveying as they went into the cave. This worked with two of the groups, but the third fell apart. Two went off with the surveying gear, but not surveying, leaving the other two behind. We found this out when, after surveying for an hour, the two who were left behind found us with the news that they had found the connection with Llueva. It was decided that our passage survey could be left as the connection to Llueva took priority. We had no idea of the whereabouts of the two members of the other team with the surveying equipment. So we started our survey from the agreed station in the main chamber and progressed to the connection. We entered the large passages in Llueva and went on a sight-seeing trip and it was not until we were returning, after completing the survey, that we met with the wayward duo. They then proceeded to harangue us as we had surveyed 'their' passage. A violent argument took place; it was fortunate that a vertical drop of 4 m separated the two main protagonists as they would of hit each other. This section is now Argument Passage on the survey.

On this second exploration into the cave with twelve people we had still not completed all the obvious leads. These and other minor passages were followed up a few days later, giving two further connections to Llueva and a total of 3 km of passage.

Only one short length of wall has any decoration, this had been caused by water flowing from a now dry roof inlet. Generally the rock was a dark brown colour and in one passage was extremely soft and friable. Mud films and deposits are common, especially in the first part of the cave and in the new section prior to the large passages. As this is the sink for the valley, the mud is deposited when the floods subside after the winter and spring rains have eased. The above ground river can back-up after heavy summer rains, blocking the cave entrance. It had flooded the northern end of the valley, effectively cutting off the village and nearly stranding the expedition one year.

The water from the Matienzo valley resurges in the one remaining valley not yet connected to the system. In addition there are still many shafts and holes which have not been entered. Perhaps another afternoon stroll by YOU will bring significant discoveries!

Ian Chandler