MATIENZO CAVES PROJECT
Matienzo 2007

Cave exploration around Matienzo during 2007


February trip
   A small number of people visited for a few days around the English half term and were rewarded with sunshine and temperatures touching 20C at times, although the strong wind and hailstones caused some lack of sleep on at least one night.
A number of holes were documented to the west of Alisas. One shaft (site 2629) was explored to a choke at -26m (on a trip to retrieve a dropped Disto) and the others await exploration (see below). In Cueva del Campo (site 76) in the Cubija valley, a close look at the gours and low overhangs revealed a number of bones and pottery sherds which are now shown in the cave description. Some of the pottery sherds seem to come from a pot similar to one from Cueva AER in the Soba valley, with dots and lines on the black pottery surface.
   On the exploration front, a small passage at the entrance of Cueva del Campo was excavated to link with the nearby site 1403. This is turn was re-explored and a hidden 15m drop revealed along with other leads to push.
   In Cueva del Agua (site 59), the bone breccia on the route to the second entrance was re-examined. The site could be an ancient hyena den, occupied over many years, rather than a natural animal trap or stream sink and wash-in. In the main chamber, some red/black pottery was discovered up a climb near to the bone breccia passage.

 The list below shows links to those 24 sites which were extended or newly discovered during February 2007, or which have had surveys updated, entrance photos or movie clips added, or entrances repositioned with a GPS. Also included are other sites which may have had similar updates through recent corrections and contributions.

Alisas 2623 shaft; 2624 shaft; 2625 cave; 2626 shaft; 2627 shaft; 2628 shaft; 2629 shaft; 2630 shaft;
Cubija 1403 cave;
El Naso 59 Molino, Cueva del; 76 Campo, Cuvia del;
La Colina 273 cave;
N Vega 0427 Lastrilla, Torca de; 0433 Acebo, Cueva de; 2611 depression; 2618 cave; 2619 dig; 2620 shaft; 2621 shaft; 2622 shaft;
Riaño 0105 Riaño, Cueva de; 644 cave; 935 Dormouse Cave;
S Vega 2587 dig;

Easter
   The weather for the fortnight started out fairly miserable and conditions on the camp site were not good - so bad in fact that one person went home early, muttering that he could trample about in mud on his farm. The fifty or so people that remained enjoyed improving weather and conditions, and some interesting cave explorations and surface prospecting. Over 3.5km of new cave passage were surveyed, the highlights being high level routes in the northern sector of Cueva Riaño, a new northerly direction for Torcón de la Calleja Rebollo (Toad in the Hole, site 258) and the removal of the skull from Cueva del Torno (site 2366). The table on the right summarises the finds.

South Vega
   In Torca de Papá Noel (1471), Hanging Death Chamber was revisited and the 30m pitch down was found to choke at the base. However a climb up turned out to be a 65m high ramp. Explorations around the entrance passages and pitches of Juan Lombrero (site 1332) added about 100m to the length. Continuing the explorations of the Cuenca caving group from a number of years ago, Torca Kunka (site 2437) at the Codisera end of the valley was forced through to a streamway. A number of digs were passed and the route remains possible at 44m depth. Also at the eastern end of the valley, Torca de Mega Mujer (site 413) was pushed and surveyed around the base of the 53m entrance pitch, opening up possibilities for extensions.
   At a high level, and in a prime spot to link the systems on each side of hill, The Volcano (site 1391) finally "went" for a short distance before halting at the usual boulder chaos. From the entrance boulders a 3m climb down and 6m pitch has entered a 5 x 5m chamber with large blocks on the floor. About 4 beds of sandstone have been passed through, one is 1.2m thick. The remaining rock appears to be mainly a type of limestone / sandstone conglomerate.
   In the Cueva Tablons dig, a solo trip to the bottom precipitated a minor collapse - boulders here need stabilising.
Another 25 holes (mainly shafts) were explored or discovered over Easter on South Vega and these are itemised in the list below.

Ozana
   The dig in Cueva Subterránea was drained using a high speed manual pump and further progress made into the hill. The excavated route is now being forced down as the roof lowers.

Alisas
   Southeast of Alisas a number of holes discovered in February were descended and all choked. More holes were also found at Easter and these also choked, although there were some large features, e.g. site 2677 where a p10 dropped into a 20m long and 4m wide rift.

Cobadal
   There was no systematic search for the downstream passages from the Sumidero to Fuente Aguanaz, dye tested last year, but there was new passage found and surveyed at high level in the main cave (site 1930). Birthday Passage was extended above the streamway for about 200m. On the surface between La Gatuna and Cobadal around the Alto de Collada, 16 shafts and digs were documented over a couple of days.

La Gatuna
   The brambly jungles of La Gatuna were braved for a day when site 2486 was explored for 21m in passage running over and beyond a dead cow that guards possible lower passage. Site 2672 was explored over the bodies of dead sheep where two routes require a ladder to enter a lower, unexplored chamber.

San Miguel
   The area high up above the Nacimiento and Cueva Cobrantes was revisited. Site 2693 (length 114m, depth 23m) was explored into chambers with fine helictites.

Cubija, Lastrillas, Seldesuto and the north slopes of La Vega
   As always, new faces and enthusiasm leads to new passage and this was true in site 258, Torcón de la Calleja Rebollo (Toad in the Hole). The end of the cave was visited on a number of occasions with a view to systematically working back from the end. However, passages were found near the end that kept the explorers occupied for the duration. The main find was 600m of descending passage heading north. The lower levels at 218m altitude (and 205m down a pitch) have lots of mud and may still be affected by the valley bottom water table at about 200m even though they are a good 1200m away and under 300m of limestone. The water from here could drain anywhere - the 200m contour to the north is over 2km away.
In the Cubija valley, a small series of holes and digs were explored up valley from Cueva de Arturo (sites 2632 - 2636) and site 72 (Sima de los Hoyos) was re-explored, photographed and detail added to the survey. This shaft is something of an animal trap with bones found in the decorated chambers at the bottom embedded in and crusted with calcite - including at least bear and dog.
   To the west of Cubija, 3 small shafts were explored. These open sites (site 2622, depth 17m, site 2666, depth 8m with formations and site 2667, 6m deep) lie only a few metres from well trodden routes, reinforcing the axiom that every metre of hillside should be walked over!
   Further to the west, sites 2661 - 2665 remain to be pushed.

Fresnedo
   Activity was high in this valley to the north of the Matienzo depression. The Caves of the Virgen associated with the Fuente de la Virgen (sites 838, 839 and 840) were reinvestigated and repositioned. Cueva de la Virgen III was surveyed and linked to Cueva de la Virgen II.
   In Cueva de la Huerta Rey (site 2519), side passages in the entrance series were pushed as was Cascade Chamber at the end of the upper level. Here, a 4m climb requires a ladder.
   In Cueva del Torno (site 2366), various goings-on occurred before the human skull was removed, with the purpose of trying to engineer an easier and less lengthy route for remains. In the Kings Dig, bad air prevented any concerted excavation in the clay. Molephoning nearby and at the site of the skull was more successful - cavers at the latter position were heard with a combination of hammering, hand-held radios and shouting on the surface, although none of the numerous surface digs were successful. An underground dig enlarged an alternative, shorter route for the skull's exit, linking with the traverse beyond the entrance series and in the process discovering 90m of passage. The skull was removed by a team of four including Jesús, the archaeologist with the government permit. Initial cleaning of the skull brought to light that the person had sustained a substantial head injury with bone damage that appeared to partially heal over. (A photo of the cranium by Jesús Ruiz Cobo is here and a closeup of the damaged area here). The skull is to be studied by Pedro Rasines, the specialist in human remains at the Altamira Museum.
   A hole up near Granny's Slippers was pushed for 127m into passage at the same altitude as the entrance.

Solórzano
   About 3km north of our caving area, we were invited to explore Cueva Toca in the hills to the east of Solórzano. This has been an important system in the past being on two levels separated by a 10m climb, although it is unlikely to be associated with the Fresnedo sites. The cave was surveyed for 266m.

Four Valleys System
   The recent discoveries at the northwestern end of Cueva Riaño were revisited and extended for over 600m. The high level passages are major routes and start to show a much more complicated history for at least this end of the 45km system. Holes above Cueva Riaño were also pushed revealing more substantial passage: Prize Cock Pot reached a depth of 13m; Cueva del Petirrojo, 14m deep and Mareerection Hole where a length of 110m was obtained through a 6m long chamber and narrow passage that ended at roof collapses. The longest new find on this hillside was site 2638 where passage has developed on two levels some 60 to 80m above known routes in Cueva Riaño. The cave, currently at a length of 205m, has digs to go at.
Above Gour Inlet, site 2686 is an undescended shaft with a good echo and a steady drip...
   The molephones were again successfully used in Cueva Hoyuca (site 107) where a bolt route up a 30m pitch at the end of Windy Inlet (near the end of the Gorilla Walk) was pushed as high as possible to a place of precarious boulders. On the surface, the molephone placed the team about 7m down below a large and deep boulder- and sediment-filled depression, which takes water. The surface team confirmed a connection by lighting a fire and sending smoke down through a small draughting hole to the roped 4-man underground team. Subsequent enthusiastic digging failed to provide another entrance to the system but this is likely to happen in the near future. The new entrance (site 2691) would allow a shorter trip to reach the far end of Cueva Hoyuca.
   In Cueva Llueva, the passages above the base of the entrance pitch were finally surveyed (31 years after discovery). An inlet passage on sandstone off the Left Hand Bypass was also revisited but this time surveyed, providing 92m of passage to a sump. The passage rising on boulders beyond the lake was re-explored but nothing new found.
   At Secadura, the area around the Boyones resurgence was visited and site 2653 discovered: "One way seems to drop to water, the other at higher level continues open out of sight...
   The Four Valleys System now has a length of over 45.3km.

Acknowledgements
   Thanks to Dany Bradshaw of the MRO for the loan of the molephones and to Brian Prewer for getting them fettled: the devices were put to successful use in Hoyuca and Torno.

   The list below shows links to those 145 sites which were extended or newly discovered over Easter 2007, or which have had surveys updated, entrance photos or movie clips added, or entrances repositioned with a GPS. Also included are other sites which may have had similar updates through recent corrections and contributions.

Alisas 2623 shaft; 2624 shaft; 2626 shaft; 2627 shaft; 2674 cave; 2675 shaft; 2676 shaft; 2677 hole; 2678 hole; 2683 shaft; 2684 hole;
Cobadal 1930 Cobadal, Sumidero de; 2679 shaft; 2680 cave;
Cubija 72 Hoyos, Sima de los; 2631 hole; 2632 shaft; 2633 cave; 2634 hole; 2635 hole; 2636 hole;
Fresnedo 163 Tejas, Cueva de las; 582 Virgen, Fuente de la; 838 Virgen 2, Cueva de la; 839 Virgen 3, Cueva de la; 840 Virgen 4, Cueva de la; 994 cave; 2366 Torno, Cueva del; 2519 Huerto Rey, Cueva de; 2539 cave; 2652 shaft; 2687 cave; 2692 cave; 2706 cave; 2707 cave;
La Collada 2714 dig; 2715 dig; 2716 shaft; 2717 shaft; 2718 shaft; 2719 shaft; 2720 shaft; 2721 shaft; 2722 shaft; 2723 shaft; 2724 shaft; 2725 shaft; 2726 shaft; 2727 shaft; 2728 shaft; 2729 shaft;
La Gatuna 2486 shaft; 2668 dig; 2669 sink; 2670 rift; 2671 cave; 2672 shaft; 2673 shaft;
La Secada 81 Carcavuezo, Cueva de; 261 shafts - 3; 2688 shaft; 2709 shaft;
Lastrillas 2712 dig;
Llueva 114 Llueva, Cueva; 2708 cave;
N Vega 1248 cave; 2622 shaft; 2661 cave; 2662 dig; 2663 shaft; 2664 dig; 2665 dig; 2666 shaft; 2667 shaft;
Ozana 29 Subterránea, Cueva; 242 Tablons, Cueva de los; 1605 cave/dig;
Riaño 105 Riaño, Cueva de; 107 Hoyuca, Cueva; 253 shafts - 2; 581 cave; 1793 shaft; 2595 Prize Cock Pot; 2596 Petirrojo, Cueva de; 2638 shaft; 2639 cave; 2640 Violent Violet; 2641 holes (2); 2642 cave; 2643 cave; 2644 cave; 2645 cave; 2646 cave; 2647 cave; 2648 dig; 2649 Mareserection Hole; 2650 Dead Goat Hole; 2651 sink; 2681 dig; 2685 sink; 2686 shaft; 2691 dig; 2710 hole; 2711 hole;
S Vega 413 Mega Mujer, Torca de la; 1332 Juan Lombrero, Cueva de; 1391 Volcano Cave; 1471 Papá Noel, Torca de; 2361 cave; 2437 shaft; 2549 shaft; 2552 dig; 2553 hole; 2554 shaft; 2654 shaft; 2655 shaft; 2656 shaft; 2657 dig; 2658 dig; 2659 dig; 2660 rift; 2694 dig; 2695 sink; 2696 shaft; 2697 shaft; 2698 hole; 2699 hole; 2700 shaft; 2701 shaft; 2702 shaft; 2703 shaft; 2704 shaft; 2705 shaft; 2730 shaft;
San Miguel 2461 cave; 2693 shaft;
Secadura 117 Boyonnes, Los; 1270 cave; 2386 cave; 2653 cave; 2690 cave;
Seldesuto 258 Calleja Rebollo, Torcón de la; 1013 cave;
Solórzano 2713 Toca, Cueva;
Trillos 1678 shaft;

Up to and including Whit
   In early April further explorations and extensions took place in site 1403 on El Naso where the depth was increased by 15m and length by 30m.
   For a week at the end of May, a small team spent most of their time on La Colina and Muela, linking site 897 to site 2588 by opening up the latter shaft, exploring it, then seeing daylight above - which proved to be the earlier discovery; eventually reaching the base of a 51m deep shaft, 2572, leaving a couple of good digs; finding an easy dig in a small cave, site 2731 and investigating the archaeological potential in site 489 and in small shelters and overhangs on the surrounding hillside. On South Vega, a previously explored walled up bedding cave, site 2587, was surveyed for 28m.

The list below shows links to those 9 sites which were extended or newly discovered after Easter and over Whit 2007, or which have had surveys updated, entrance photos or movie clips added, or entrances repositioned with a GPS. Also included are other sites which may have had similar updates through recent corrections and contributions.

El Naso 1403 cave;
La Colina 99 Alpine Chough Pot; 897 shaft; 2572 shaft;
Muela 489 cave; 2588 shaft; 2731 dig;
S Vega 1246 cave; 2587 cave

Summer
   The highlight of the summer was the exploration in Cueva Llueva, providing new leads and new evidence for levels of development at the Cillarón / Trident Passage level. Nearly 3.8km was surveyed here so that the length of the Four Valleys System is now just a kilometre short of the 50km. In the Sumidero de Cobadal, 830m were surveyed, mainly in inlets apparently bringing in water from a valley to the south west. The passage surveyed in the summer totalled 5779m.
   The weather was generally OK until 21st August when prolonged heavy rain prevented exploration in Cueva Llueva and flooded the fields in Matienzo.

South Vega
   At Cueva del Zorro (site 345), the cave entrance was enlarged for normal-sized people and the cave re-explored - the first visitors for 25 years. Photos were taken but the draught remains elusive.    The Dairy Dig (site 1189) was excavated as was Dead Fox Passage (site 1253). These underground, draughting digs are close to each other in an area where there is little known passage and both are draughting at the end of short lengths of 1.5 - 2m high "proper passage".
   Higher up the hill lies the entrance to Cueva Lammas (site 1325). The new mobile phone mast has been built just in front of the entrance shakehole and half of the depression has been taken up with a wall of large rocks. The entrance itself appears to be still open. Site 1342, at the end of the TV mast track was revisited and recognised as a potential dig. Site 2360, situated about 100m WSW of Cueva Lammas, was opened up to allow exploration down a 17m pitch to a choke.
   Lower down, behind the old Vega Bar, the goat shelter to the east of La Cuevuca (site 177) was finally explored to a length of 12m and given a number (site 2682). Also noted was a small, 4m long shelter below here (site 2637) and a small, second entrance to La Cuevuca.
   Tablons (site 242) was excavated at the base of the final climb down. About 100m downstream of the Comellante resurgence (site 40) some of the water was seen as a tiny whirlpool sinking in the stream bed (site 2755). Last year, during low water conditions, all of the water disappeared at these points. The farmer tries to keep the sinks blocked so that water flows all the way to Cueva del Agua.

Arredondo
   Little new exploration has been carried out in Cueva Vallina (site 733) this year. The maze next to Shatter Passage, near the bottom entrance was surveyed generating 110m of passage to include in the length of 31201m. The survey has been updated and various levels coloured to aid interpretation.

Seldesuto
   This area hosted a number of activities over the summer. In Cueva Arenal (site 35), a trip down beyond the Foam Dome reconfirmed the complexity of the boulder chokes and the difficulties of progressing in this draughting enigma. The right hand cave was confirmed as an prehistoric site when flints and bones were discovered by Spanish archaeologists. A permit may be asked for to allow further excavations.
   After the Foam Dome was re-explored, interest was rekindled for searching the area beyond the end of Arenal. As a result, site 2740 was excavated over a couple of days and explored down a 12m pitch to a choke. Site 2741 was also discovered in the jungle below - a walk-in entrance to a chamber with some ancient remains of two human infants. The excavation and dating of these remains will also need a permit.
   Higher up the hill, a draughting sink (site 2743) was discovered and remains a good dig. A couple of other sites (2744 and 2753) were dug.
   On the other side of the valley, high above site 258, Torcón de la Calleja Rebollo (Toad in the Hole), site 2744 - in a shakehole with a 10m high scar - was recognised as a good digging site.

North Vega and El Naso
   Cueva del Bosque (site 373) at the end of a blind valley was re-explored, extended and surveyed, although some of the original 1982 explorations were not entered. The cave is in an excellent position but has yet to realise its potential.
In the Lastrillas area, site 2663 was descended 4m to a possible dig. Exit from the hole was made up a rift that linked in another entrance. Other small sites (2734, 2735 and 2736) were also discovered in the area.
   On El Naso, three sites (Cueva de Asiul, site 61; Cueva del Sotarraña, site 73 and site 993) were repositioned using GPS and photos were taken in Cueva de Asiul. Two new small caves were also documented (sites 2689 and 2799).

Ozana
   Work has started on the resurvey of Cueva Risco (site 25).

Muela and Mullir
S   ite 299 was repositioned, re-explored and photographed. Two undocumented sites were discovered on a walk to the top of Mullir. Site 2797 is an unexplored 10m deep shaft on the west side of the Hoya de Yusa. Site 2798 is an unexplored 5m drop within a few metres of the summit of Mullir. Horsefly Pot (site 2733) was dug out to reveal a choke 5m pit. On the lower northern slopes of Muela, site 2747 is a small cave with bones and site 2748 is a choked 2m deep hole.
   There is now a track being built to provide pylons for a power line above the farm houses near Tora Bora, site 1786. This track currently ends about 300m from the lip of the Hoya de Yusa and possibly 100m below. This 4-wheel drive track would obviously aid the carry-in for further explorations on Muela and Mullir.

La Secada
   A small extension was made in Cueva del Anío (site 151) where a small chamber was entered under the right hand wall. Cueva de la Orilla Mijeo (site 91) was relocated and re-explored. Torca de JR (site 366) was re-explored and avens off the shaft looked at. At the base of the hole is a draughting continuation that could be enlarged. The draught could be heard in the distance.
   Mustard Pot (site 2742), some 120m southeast of site 415, was dug into to reveal a sloping 9m pitch with a small chamber and a possible dig. The site had a lot of yellow lichen.
   Fuente Ramera, below La Colina, was finally numbered (site 2800). A plaque and mechanical pump has been installed just above the resurgence on the west of the track in memory of José Antonio Carro Solana. Another smaller resurgence was documented near to El Camino (site 2801).

Cobadal - Fuente Aguanaz system
   The search for caves associated with the Cobadal - Fuente Aguanaz system continued.
In this "new" area of Ideopuerta and Moncobe , site 1972 was descended 12m to a choke. Various digs were noted (sites 2749, 2750 and 2751) and 2 caves (sites 2771 and 2796) and a shaft (site 2772) remain unexplored. Other sites are itemised below.
   The areas of San Antonio and Barrio La Mina lie over the end and to the west of Fuente Aguanaz (site 713). Site 2784 is a 10m deep excavated pitch with a good echo into a choked chamber. (This site was explored at Easter but only documented now.) Site 2781 is a tiny cave under sandstone and site 2782 is a large shakehole filled with hundreds of tyres. There is a small cave on the south side that continues for about 4m.
   In and around the Cobadal depression various sites were worked on. The dig in a prominent depression at site 921 was opened up and a 52m long remnant entered. A number of small caves and digs were noted - sites 2774, 2775, 2776, 2777, 2778 and 2779. In Snottite Cave (Cueva de las Esquimaduelas, site 1874), work to enlarge the end took place over a number of days through Owl Neck Crawl. This currently ends, after a 5m high rift, at a 15cm high crawl.
   In the Sumidero de Cobadal (site 1930), further inlets were pushed off Just an Inlet and a small passage was pushed from near Loop Pitch nearly to the entrance. A maze off Meander Passage was also pushed and surveyed. The pitch was bypassed by following a hole on the right wall part way up the rift before the pitch. More than 830m was explored in the cave, taking the length to 7362m.

Fresnedo
   The canal at the bottom of Cueva de Huerta Rey (site 2519) was pushed with an airbed to a blank wall. The tight passages before here were surveyed giving a total length to the cave of 633m. Above Cueva del Torno (site 2366), the bone discovered last year in Pig Nut Pot (site 2523) and thought to be a human femur was checked out by Jesús the archaeologist and found to be a bear bone. (A bear bone is flatter with a more rectangular cross section compared to a more circular human femur).
   Bumble Cave (site 2692), part of the Fuente de la Virgen caves complex, was excavated to give 10m of passage to a draughting dig.
   In an area 500m to the NW of the church, a number of sites were explored. Sites 2737 and 2738 (Slaves' Cave) were nearly connected in dip and strike passages, reminiscent of passage control in the nearby Cueva de Regato (site 672). The total length of these holes was 164m reaching a depth of 20m. There is still a digging possibility in Slaves' Cave. A nearby dig (site 2769) requires a return with a ladder.
   A number of sites were documented above the Nacimiento del Campiazo (site 1106). Sites 2760, 2761, 2762, 2763, 2764, and 2765 are all digs with encouraging indicators, e.g. strong draught or passage visible beyond a boulder. Next to the main road, some rocks were removed from the draughting dig 2415. This site is giving encouraging signs and should repay further work.
   Further up the hill, higher and to the west of Cueva del Torno entrance, the walk-in entrance to site 2766 proved a disappointment, choking with calcited boulders after 11m. Along the same scar, site 2767 requires more digging to enter a low crawl.
   About 200m south of the church, site 2773 was described as a bramble-filled rift with a squeeze down into the unknown.
On the north of Fresnedo, site 2739 was surveyed in phreatic passages and tubes to a length of 185m and a vertical range of 20m.

Secadura
   Near The Fox Hat (site 2025) , on the northern slopes of the Secdura valley, site 2501 was enlarged and descended 4m to where further digs hinder progress. In The Fox Hat, progress is being made along a narrow, draughting rift with passage visible beyond.
   On a day out with Spanish archaeologists, a number of caves were visited in the small hill containing Cueva de Otero (site 119), a gated cave which has important prehistoric deposits. Cueva Otero 2 (site 2787) was entered, as was Cueva del Otero 4 (site 2788). Cueva del Otero 3 could not be found in the dense jungle.
   Further down valley, Cueva de los Tres Rios (site 2789) was entered and surveyed for 18m.  A number of oyster shells were found just inside the entrance, suggesting a possible prehistoric midden. A small cave (site 2790) around the side of the same outcrop was entered for 3m.
   A small group in September opened up site 1103, against a "mini Malham Cove", and excavated along a bedding after a chamber.

San Mames
   Cueva Domingo Lopez (site 729) was visited with Spanish archaeologists. The prehistoric pottery was noted and an extension to the cave, previously explored by others using a ball of string, was surveyed in well-decorated passage.

Four Valleys System
   Continuing the re-exploration and re-survey of the Four Valleys System, a team took a scaling pole into Cueva Llueva (site 114) to climb an aven in the Right Hand Fault Passage off the lake. They found carbide at the top of the climb. A card index / log book search found that the aven had been free-climbed in 1979 to a boulder choke. This summer, boulders were removed from the choke allowing entry, some 80m above the orignal climb, to a large sloping chamber with plan dimensions of 20 x 30m and two passages leading off. Subsequent explorations dropped back down to river level finding an extensive set of tunnels including a parallel, wet weather overflow passage. High level passages entered are at the same level as the Trident Series in Cueva Hoyuca (site 107) and the 50m wide passage at the bottom of Torca de Cillarón (site 109). In a middle level, a large, flat-roofed passage (up to 50m wide) heads east-west at an altitude 40m below the lowest point in Cillarón.
   On a pushing trip in the lower level passages, near the end of a traverse, a flash bulb was found just opposite where a small passage entered. This point was subsequently found by burrowing down through boulders near the columns in the Right Hand Fault Passage about 25m away from where the pole had been used two weeks before!
   During walks over the top and to the north of the new extensions, site 2785, a possible 30m pitch next to a track, was found and has yet to be descended. Site 2792 is a resurgence which may dig, but of more interest below is site 2793 a choked, 5m depression where the water sinks. Two hundred metres to the northwest, Hazel Cave (site 2794) is an unexplored crawl.
   Nearly 3.8km were surveyed in the Life, Universe and Everything extensions and there are still leads to push. The length of the whole Four Valleys System is just over 49km.
   The entrance pitch to Cueva Llueva was derigged after a couple of days of heavy rain, when the fields next to the river in Matienzo were about to flood. The river at the base of the pitch was a torrent with the route up the boulder slope into the main tunnel almost cut off. The water was seen to rise a couple of inches in half and hour. There was also a waterfall cascading down from above the entrance and sinking in the floor of the depression.
   Other holes lying in the presumed catchment for the system were also investigated. In the Llueva valley, site 2746 is a small unentered cave. Over the Riaño end of the system a number of sites were found or extended. The proposed "new entrance" (site 2691) at the top of a bouldery aven over the Gorilla Walk collapsed after the excavations at Easter and some stabilising and shoring is now required before a connection can be made. The 205m long Bog Hole (site 2638), which lies over the new extensions in Cueva Riaño (site 105), was pushed on both levels to a big choke on shattered joints. Further up the hill,    Mareserection Hole (site 2649) was extended at the base to a hands and knees crawl ending at a squeeze. Further south on the same hillside, Blow Dry (site 2745) still requires lots of work to follow the draught. Prophet's Cave (site 2685) was dug and nearly 100m of rift passages entered above the start of 3rd River Inlet in Cueva Hoyuca. Above Gour Inlet, Shag Pot (site 2686) was descended 10m and explored for about 40m to various digs. Much lower down, over the downstream end of Cueva Riaño, site 2783 is an narrow slot with a very strong draught.

   The list below shows links to those 136 sites which were extended or newly discovered over the summer 2007, or which have had surveys updated, entrance photos or movie clips added, or entrances repositioned with a GPS. Also included are other sites which may have had similar updates through recent corrections and contributions.

Arredondo 733 Vallina, Cueva;
Barrio La Mina 2784 shaft;
Bosmartin 2795 Duck Pot;
Cobadal 921 cave; 1874 Snottite Cave; 1930 Cobadal, Sumidero de; 2774 cave; 2775 cave; 2776 dig; 2777 shaft; 2778 shaft; 2779 shaft;
El Camino 2801 resurgence;
El Naso 61 Asiul, Cueva de; 59 Molino, Cueva del; 73 Sotarraña, Cueva del; 155 Lara-Lennon, Cueva de; 993 cave; 2689 cave; 2799 cave;
Fresnedo 126 Fresnedo 1, Cueva; 0841 Fresnedo 2, Cueva; 0983 cave; 2519 Huerto Rey, Cueva de; 2523 Pig Nut Pot; 2692 Bumble Cave; 2737 shaft; 2738 cave; 2739 cave; 2760 dig; 2761 dig; 2762 dig; 2763 dig; 2764 dig; 2765 dig; 2766 cave; 2767 dig; 2769 shaft; 2773 cave; 2780 dig;
Fuente las Varas 104 Fuente las Varas, Cueva de;
Ideopuerta 1972 shaft; 2749 dig; 2750 dig; 2751 dig; 2768 shaft; 2771 cave; 2772 shaft; 2796 cave;
La Secada 81 Carcavueso, Cueva; 91 Orilla Mijeo, Cueva de la; 143 shaft; 144 shaft; 151 Anío, Cueva del; 366 J.R., Torca de; 707 shaft; 826 dig; 2742 Mustard Pot; 2752 cave; 2770 dig; 2800 Fuente Ramera;
La Vega 2755 sinks;
Llueva 114 Llueva, Cueva; 1464 cave; 2733 Horsefly Pot; 2746 cave; 2747 cave; 2748 cave;
Moncobe 2756 shaft; 2757 shaft; 2758 shaft;
Muela & Mullir 299 cave; 2797 shaft; 2798 shaft;
N Vega 373 Bosque, Cueva del; 1248 cave; 2663 shaft; 2734 shaft; 2735 shaft; 2736 cave;
Ozana 25 Risco, Sima-Cueva del; 0242 Tablons, Cueva de los;
Riaño 107 Hoyuca, Cueva; 2638 Bog Hole; 2649 Mareserection Hole; 2685 Prophet's Cave; 2686 Shag Pot; 2691 dig; 2745 Blow Dry; 2759 shaft; 2783 dig;
S Vega 177 La Cuevuca; 345 Zorro, Cueva del; 1189 Dairy Dig; 1252 cave; 1253 cave; 1325 Lammas, Cueva; 1342 cave; 1391 Volcano Cave; 2360 shaft; 2637 cave; 2655 shaft; 2682 cave; 2732 dig; 2802 hole;
San Antonio 2781 cave; 2782 cave;
San Mames 729 Domingo Lopez, Cueva de;
Secadura 689 Andando, Torca; 1103 cave; 2501 dig; 2786 dig; 2787 Otero 2, Cueva del; 2788 Otero 4, Cueva del; 2789 3 Rivers Cave; 2790 cave; 2791 shaft; 2792 resurgence; 2793 cave; 2794 Hazel Cave;
Seldesuto 35 Arenal, Cueva del; 372 cave; 430 cave; 546 shaft; 1304 shaft; 1306 dig; 2311 cave; 2740 cave; 2741 Baby Skull Cave; 2743 sink; 2744 dig; 2753 dig; 2754 shaft;
Solorzano 2713 Toca, Cueva; 2415 dig;

Autumn & Christmas

    Visits occurred in October, November and December.

   On the north side of Cueto, site 128, Torca Espina was revisited, photos taken and detail filled in on the survey. There are possibilities for extending the very large passage at the base of the steep slope. Site 2807 was noted on a walk up from Cruz Uzano to Mullir.

   In Cueva de Coberruyo on Enaso, a number of small extensions were found and amendments made to the survey. A possible sighting of the rare Greater Noctule bat (Nyctalus Lasiopterus) was reported. Further to the east, sites 1348 and 1349 were connected and identified as a good draughting site. Another 50m to the east, a possible walled rock shelter was identified - site 2803. Further down the hill, and above Cueva Asiul, site 2805 needs enlarging to explore a 4m shaft with a red floor. Cueva Asiul was visited on a number of occasions: black wall marks were noticed near the entrance, and charcoal was found on the floor throughout the well-decorated passage. In an alcove at the end charred bones with possible implement marks were photographed. Some time was also spent unsuccessfully looking for Cueva Perlas and site 355 although these were eventually refound and Perlas photographed on a couple of occasions. Nearby caves (site 354 and 1271) were GPSed some 40m higher than originally placed on the maps. It now seems that the new digital map has corrected an error on the old map that had the base of the Coberruyo cliff line at 300m altitude. The corrected altitude is 350m and this will inevitably "move" a number of entrances as they are GPSed. To the west of Coberruyo, site 2804 was documented as a possible archaeological site with bones and pottery. On the top of El Naso, site 2785 was discovered - a dig into a 5m deep rift. Site 1294 was searched for at least three times and is still missing!

   In the Four Valleys System, Cueva Riaño was extended by 248m up a high level route, 89cents Tinto Extension, pushing the length of the 4VS to 49.3km. This sets off in a series of climbs and traverses heading southwest from the vacinity of Cat Paw Print Passage, apparently ending 3m below the surface some 70m from the nearest site in the "Hoyuca-Riaño corner". Site 689 on the Llueva / Secadura hillside, refound in the summer, was confirmed as Torca Andando and a nearby tube, site 2786, was enlarged and pushed to the top of a pitch with a drop of 5 seconds. Later in November, this was further enlarged and confirmed to link with Andando as rocks thrown down the long drop were heard falling at Andando entrance. The draught may be coming from a tube across the top of the drop. The bouldery remnant (site 1103), above the main resurgence at Secadura, was surveyed for a length of 45m.
   The calcited choke at the end of Cueva del Zorro (site 345) was attacked, entering a small chamber with a very loose roof of choss that will require a long bar to drop. The cave was resurveyed. There is a suggestion that the cave may be heading back to the surface at the choke.

   The new substantial track for installing electricity pylons on the north side of Muela was investigated from the top down. The roadway has been extended since the summer and the current highest point is just past the top entrance to Cave of the Wild Horses (site 647). The shakehole containing site 746 has been filled in and it could be that site 299 has been obliterated.

   Cueva de Fuente de la Pila (site 486) was visited and photographed. Flints were found in the entrance sediment.

   A number of sites were found and inspected over the supposed Fuente Aguanaz system. At Ideopuerta, first the vegetation was removed at site 2796 and then the entry in the card index - no cave and no digging potential. At Barrio La Mina, sites 2833 and 2835 were seen as possible digs, site 2836 was spotted as a small cave entrance just below a hilltop and site 2834, Pallet Hole (due to the nature of the shakehole contents) was found draughting in strongly with stones falling 12m.
At Camposdelante, site 2433 was excavated to a loose p5 into a 32m long rift. Site 2434 is an undescended 5m deep, slab-covered drop with an echo that requires further digging.
   The deep shaft (site 2768) at Ideopuerta was again looked for without success. while site 2772 was descended down p8 and p4 to a draughtless choke with little promise. Site 2830 was dropped to a depth of 9m with short passages in both directions.
   At San Antonio, site 2831 is a small resurgence with a sink that requires vegetation removal equipment.

   The late December visit merged seamlessly, over new year, into the January 2008 trip, a new log book and the Matienzo 2008 article. (In early February 2008, the updated survey of Cueva Llueva (png file, 1.3Mb), showing the major extensions discovered last summer, was completed in Tunnel by Paul Fretwell in time for inclusion with the Matienzo '07 article in Speleology. The draft colour version can be found here.)

   The list below shows links to those 50 sites which were extended or newly discovered during October / November / December 2007, or which have had surveys updated, entrance photos or movie clips added, or entrances repositioned with a GPS. Also included are other sites which may have had similar updates through recent corrections and contributions.

Arredondo 733 Vallina, Cueva;
Barrio La Mina
2070 dig; 2784 shaft; 2833 dig; 2834 Pallet Hole; 2835 dig; 2836 cave;
Camposdelante
2433 shaft; 2434 dig; 2828 dig;
El Naso
61 Asiul, Cueva de; 74 Perlas, Cueva de las; 138 Coberruyo, Cueva de; 354 cave; 355 cave; 913 Reyes, Cueva de; 1145 shaft; 1271 cave; 1294 Epiglottis Cavern; 1348 cave; 1349 cave; 2785 shaft; 2803 cave; 2804 cave; 2805 shaft; 2806 shaft;
Fresnedo 2366 Torno, Cueva del; 2764 dig; 2765 dig;
Fuentecil 2832 dig;
Ideopuerta 2768 shaft; 2772 shaft; 2829 dig; 2830 shaft;
Ozana 486 Fuente de la Pila, Cueva de;
Muela 128 Espina, Torca de la; 299 cave; 647 Wild Horses, Cave of the (top entrance); 746 shaft;
Mullir 2807 shaft;
Riaño 105 Riaño, Cueva de;
S Vega 345 Zorro, Cueva del; 2802 hole;
San Antonio 2831 resurgence & sink;
Secadura 689 Andando, Torca; 1103 dig; 2386 cave; 2387 resurgence; 2388 cave; 2786 Three Idiots


Juan Corrin, March, May, June, September , November , December 2007, January, February, April 2008