Matienzo 2012

Cave exploration around Matienzo during 2012
An (out-of-date) map with area names can be found here

January & February

   The highlight of this period (so far) was the further extensions in Cueva-Cubío del Llanío (Cold Store Cave) at Riaño. Four Danes spent 4 days in the system, pushing leads discovered on their autumn trip. Part way down the Cross Roads Shaft, the West Wing was surveyed 60m to a choke. Across in the East Wing, the team dropped 13m down Eels Shaft to enter a passage that headed south through a grotto to break out into the side of a shaft with the passage continuing on the far side. Unfortunately, the 8 bolt traverse was not worth the effort as the passage soon closed in. The survey can be seen here. The "Eels extensions" produced 164m of hard won passage. (Video).
   On a day when it was too wet to go up The Aven (there was a waterfall coming down it) some progress was made at the draughting sand and calcite dig at the southeast extremity (station 10_04.01 on the survey)
   With the permission of the AEC Lobetum group we were able to have a quick exploration, survey and video in Torca CEZ in the Hoyo de Mortiro above Riva. This 2.3km system is coming close to Cueva del Coverón and parts of the cave have the look of Coverón about them. The brief survey highlighted the weaknesses of the Cuencan cavers surveying technique (to 5 degrees, and no clino) and prompted a request to carry out a resurvey of CEZ and Coverón. Hopefully, this will be a joint exercise between the two adjacent groups and further exploration and dye testing may find a second streamway to feed the second rising in the Hoyo Mortiro.
   New photos and video of the autumn excavation of the pottery in site 3167 on the the Matienzo-Arredondo ridge have been uploaded.
   Discussion about previous regional underground drainage routes was again raised in the Google Group.

  Other additions to the Matienzo Caves web site:
- Footleg has completed both an interactive virtual tour of the Astradome in La Hoyuca and a Therion file (downloaded as a zip file) which shows the caves around San Antonio, Hornedo and Cobadal beneath a 3-dimensional landscape.
- Pete Smith has updated the survey around the Squirrel's Passage area of Reñada and updated his Trees of Matienzo Power Point presentation.
- Terry Whitaker has produced a draft version of the hydrology in and around Cueva Hoyuca as part of the 4 Valleys System. (He is working on a more detailed version of the entrance series.)

   The list below shows links to those 21 sites which were extended or newly discovered over January & February 2012, or which have had surveys, references or descriptions updated, entrance photos or movie clips added, or entrances repositioned with a GPS.

Cubija 75 Picón, Simas del; 2167 Frank's Cave;
Fuente las Varas 101 Canal, Cueva de la; 104 Fuente las Varas, Cueva de; 1614 cave; 1615 cave;
Llueva 114 Llueva, Cueva;
2 Coverón, Cueva del;
Riaño 102 Castañas, Cueva de la; 105 Riaño, Cueva de; 106 Riaño, Torcón de; 107 Hoyuca, Cueva; 575 Resurgence Riaño; 1617 cave; 1618 dig; 1666 cave; 2691 Giant Panda entrance; 3234 Llanío, Cueva-Cubío del;
Riva 3603 CEZ, Torca;
S Vega 48 Reñada, Cueva-Cubío de la;
Seldesuto 3167 cave;

Easter period

   Over the main span of the expedition there was one day without rain. Indeed, Santander had it's 3rd wettest April in the last hundred years. Despite the disheartening weather, the full range of caving trips were undertaken. Digs, pushing, diving and surveying trips were all successful, with over 3.5km surveyed and more than 90 new sites identified. Most new passage was surveyed in Cueva Hoyuca where more than 1.2km was discovered in the Sima Baz section in the entrance series and off Diversion Chamber further into the cave. Resurveying in this cave and Cueva Ruchano / Espada has produced many leads.
   Explorations in El Cubillón at Moncobe progressed slowly but avens were climbed and over 800m of passage were surveyed.
   Plans to enter the Matienzo valley main sink, Cueva Carcavueso, were scuppered when continuous rain sent water down the overflow channel at the main sink to drop down the entrance, perhaps 5m above normal water levels.
   A number of digs progressed over the Easter period - most of these are not detailed below but do appear in the site list.
   A number of people were attacked by ticks. This Lyme Disease poster may be informative.

Southern Sector
   Although conditions started off well for Rupert Skorupka diving in Squirrels Passage, in Cueva-Cubío de la Reñada, they deteriorated after the rain started. In the end, he was able to progress downstream a short distance beyond last year's limit and surveyed back to the end of the 1982 survey. The data for the dive remains in the cave for the moment.
   Rupert also dived in Comellantes, investigating alcoves in the left hand wall.
   High above Seldesuto, a number of sites were positioned with GPS and, in the process, a number of new (and undescended) ones found. See sites 570, 571, 572, 659 and sites 3619, 3620, 3621, 3625, 3626 and 3627. There's a good day or two exploration just to clear up this small area.
   High above the northern end of Cueva Vallina, draughting site 1340 was excavated to pitches of 12 and 15m, ending at a draughting choke. The nearby site 1220 was also explored to a tight, draughting rift "that seems to open up".
   An afternoon walk just above the Dairy Dig area revealed 11 new holes that need exploration (sites 3670 - 3680).

El Naso area west to Las Calzadillas
   Toad in the Hole was tackled up as far as Girlies Day Out and the aven noted in 2008 climbed. The complex area was explored up "lower active", "higher active" and "fossil" avens with the recommendation that a further 30m climb should be tackled up the "higher active" section. Photos were taken in and around Cloud Nine and video filmed, revealing a very nice section of cave.
   While these explorations were in progress, an open shaft (above Toad) close to a property being rented at Las Calzadillas by some members of the expedition was revealing a going system. Unfortunately, the initial excitement in site 3638 was short lived after crawls with chokes were discovered 55m down. Another open hole at Las Calzadillas, site 2923 first noted in 2008, also choked. This pot finished the day after exploring to "a balcony overlooking a large chamber". The chamber was choked where a small trickle of water flowed into muddy boulders at 35m depth.
   In the Cubija valley, a tight rift in Simas del Picón was enlarged in an attempt to connect with the recent Cueva Morenuca extensions below. To the west in another picturesque valley, site 3622 continued excavation revealed a small crawl into a chamber. Subsequent exploration dropped 3 pitches to a depth of 59m and length of 122m.

The Northeast Sector including the Four Valleys System
   Cueva Hoyuca is continuing to be the focus for a number of persevering cavers. By concentrating on small sections of cave while resurveying, smaller passages and leads are being investigated. Some may start small but recent finds have broken into large extensions. As well as substantial amounts of resurveying at Easter, over 1.2km of new passages were surveyed in the Sima Baz area and off Diversion Chamber.
   The Cueva Ruchano / Cueva Espada / site 3222 complex may finally have been completely explored and surveyed (although upstream could "go"). First explored in 1975 (when a Bronze Age sword was found in the underground stream) the system now has a pitch entrance and an old, high level series. The system is over 2.1km long and the through-trip connection from top sink to resurgence is now through a tight, unstable, bouldery section.
   In Llueva, the walk-in entrance at site 3691 quickly gave way to crawls 17m higher than the entrance beds in Cueva Llueva. The entrance depression to Cueva Llueva was found to have become a dump for tyres and road contractors' material. The protruding bed edges appear to be coated with limestone dust and the base has a layer of mud. Open holes in the depression were documented.
   A number of "old" sites were GPS'd around the Mushroom Field area where Carcavueso starts and the Trident Series passages from Hoyuca finish. With the new Four Valleys survey progressing towards the Trident Series, it is hoped that new Nicola phones (soon to be purchased) will aid communication and positioning of stations and sites above and below ground, especially in this area. The draughting site 603 may be a "back door".
   As flooding in the valley ebbed and flowed, it was noticeable that certain resurgences were produced large quantities of clean water compared to the Matienzo river which always runs brown when in flood. Resurgences that were running clear included the Ramira resurgence (site 2800) and site 2801.
   On Muela / Mullir, site 3504 next to the track on the walk up, was found to enter a chamber with evidence of some capping in a tight section above a short drop. This will need further investigation. Site 2465 was finally explored after 6 years but soon closed in at the base of a small chamber.

Northwest Sector
   The highlight of the northwest area was the exploration in site 2538, El Cubillón at Moncobe. Over 800m of new passages were surveyed, taking the length to 1584m. A number of avens were climbed but the hoped-for higher level passages have yet to be entered. A number of leads remain, not least a downstream sump. The cave is in the middle of nowhere and has apparent potential in all directions.
   Other holes investigated at Moncobe included site 3649, a strongly draughting entrance leading through a chamber to small holes; various holes (sites 3650 and 3651) near a 30 - 40m wide amphitheatre; site 3655, a rift at the base of a cliff where a small window needs enlarging to access "further space"; site 3693, a 3m climb down into a 20m long, choked cave; a number of other small sites and a number of draughting digs.
   High on the opposite hillside, the impressive entrance rift at site 3420 (Washing Machine Hole) has been excavated and surveyed for 134m down to 24m depth. This going hole has at least as much potential as El Cubillón.
   A large, open shaft at 500m altitude (site 3664, near Las Calzadillas) was descended to a depth of 20m before ending at a draughting dig.
  On the southern slopes high above Cobadal a number of interesting sites were documented (3681 - 3687 and site 3694). Shaft 3681 drops 8m and continues down a Disto'd 14m. Sites 3682, 3683 and 3684 remain undescended and site 3685 is a strongly draughting hole that is being excavated. On a common rift with site 3682 and 3683, site 3694 was descended 8m into cross rifts with no obvious way on.
   On the valley bottom at Camposdelante, just above Duck Pond Sink, site 3215 continues to be excavated, while continued exploration in site 3359, 200m above, dropped a 12m pitch to a choked flat floor.
   In Cueva del Nabo, at the base of the La Gatuna depressions, the high level passage above sump 2 ended in "a very small stream passage where "no way on looks any good". Upstream sump 2 was dived by Martyn Grayson and Dan Hibberts to -14.6m where a steep, sandy, tight incline needs digging. Eight hundred metres west, Farmer's Hole, site 3573 was pushed 80m to "cracks". To the east of La Gatuna, site 3636 goes 6m to a choke but has a pitch which needs dropping.
   Between Nabo and Torca la Vaca, sites 3641 - 3647 were investigated. The largest, site 3645, was an excavated badger sett, surveyed in rifts for 24m. Some work was carried out in holes near to Torca la Vaca. Honeymoon Pot was stabilised and the bottom pitch cleared then descended to a choke 10m down. This needs further work and further stabilisation higher up the shaft. Nearby, site 3668 turned out to be a 30m long, well decorated through trip, very tight in the middle.
   Some effort was expended in the far northwest, around the Fuente Aguanaz area. In site 3283, Invisible Cave, Martyn Grayson and Dan Hibberts extended the system upstream by surveying nearly 250m beyond sump 2 to sump 6 and explored a further 30m or so through to the start of sump 8. Between sumps 4 and 5, a large aven and possible passage were seen which may eventually be joined to nearby holes above, eg site 3011.
   Among a number of sites found in the recently cleared woods around Maze Cave (site 3268), site 3660 was explored down a very loose p23 into a 20m long rift. Higher level routes choked.
   After the main expedition period finished, Jim Lister and Colin Hayward pushed upstream (in flood conditions) in Wild Mare Cave (site 767) through Sump of the Wild Eels into the known chamber containing sump 2 and a possible connection with Torca la Vaca. On the fifth day of diving, this time from the downstream sump at the base of the Buttermere Pitch in Torca la Vaca, the pair pushed through a large breakdown area to join with Wild Mare at the first rift on the north side of the upstream end of the Wild Eels Sump. Jim and Colin also dived upstream at the bottom of the Buttermere pitch breaking through into the downstream Whitworth Series. A video of their exploits can be seen on YouTube. The length of the Torca la Vaca cave system is 15222m.

   Other additions to the Matienzo web site include
- a lox file (for use with the Loch viewer of Therion) created by Paul Fretwell of the 4 Valleys System with some surrounding caves (download as a zip file) under a photo landscape (Version 2 uploaded 23/4/2012).
- The Oñite-Risco-Tiva System has a recalculated length of just over 10.4km. The latest Oñite-Risco survey produced by Peter Smith can be seen here.

   The list below shows links to those 172 sites which were extended or newly discovered over Easter 2012, or which have had surveys, references or descriptions updated, entrance photos or movie clips added, or entrances repositioned with a GPS.

Arredondo 733 Vallina, Cueva;
Barrio de los Urros 2917 cave;
Campo La Cruz 3209 cave;
Camposdelante 3215 dig; 3359 shaft; 3631 cave; 3663 shaft;
Cobadal 3681 shaft; 3682 shaft; 3683 shafts; 3684 shaft; 3685 cave; 3686 dig; 3687 dig; 3694 sink;
Cubija 75 Picón, Simas del; 76 Campo, Cuvia del;
El Camino 2801 resurgence;
El Naso 3559 cave;
Fresnedo 983 cave; 994 cave; 2761 cave;
Hornedo 767 Wild Mare, Cave of the; 978 cave; 979 Culebro, Fuente de; 2889 Vaca, Torca La; 2907 sink; 3357 Nabo, Cueva del; 3380 Peña Encaramada, Torca de; 3573 Farmer's Hole; 3594 Luna de Miel, Torca de; 3641 sink; 3642 dig; 3643 cave; 3644 dig; 3645 cave; 3646 dig; 3647 dig; 3668 cave;
Ideopuerta 2751 dig; 3420 shaft; 3664 shaft; 3665 shaft;
La Gatuna 3636 cave; 3637 holes;
La Secada 81 Carcavuezo, Cueva de; 86 Cuvia, La; 252 cave; 260 shaft; 603 shaft; 869 cave; 870 shaft; 871 shaft; 1063 dig; 1623 cave; 2800 Ramera, Fuente; 3628 hole; 3639 dig; 3640 shaft; 3700 resurgence & sink; 3704 sink; 3705 sink; 3706 sink; 3707 dig;
Las Calzadillas 2923 shaft; 2996 cave; 3638 shaft;
Llueva 114 Llueva, Cueva; 1986 cave; 2708 cave; 3334 Road Works Pot; 3354 cave; 3667 cave; 3688 sink; 3689 cave; 3690 cave; 3691 cave; 3701 dig; 3711 resurgence;
Moncobe 2536 cave; 2538 Cubillón, El; 3648 shaft; 3649 cave; 3650 caves; 3651 shaft; 3652 cave; 3653 dig; 3654 shaft; 3655 shaft; 3656 shaft; 3666 shaft; 3669 caves; 3692 dig; 3693 cave; 3695 cave; 3696 caves; 3697 cave; 3698 cave;
Muela 3143 cave; 3392 shaft; 3504 cave;
Mullir 2465 cave; 3618 Red Stripe Hole;
N Vega 429 shaft; 434 cave; 830 dig; 2661 cave; 3000 dig; 3622 cave; 3623 shaft; 3624 dig; 3632 dig; 3708 dig; 3709 dig; 3710 dig;
Ozana 25 Risco, Sima-Cueva del; 27 Oñite, Cueva;
Riaño 103 Espada, Cueva de la; 107 Hoyuca, Cueva; 207 Cuvia, Fuente de la; 575 Resurgence Riaño; 718 cave; 1800 shaft; 1801 cave; 2903 Church Entrance (Hoyuca entrance); 3222 cave; 3223 shaft; 3232 Ruchano, Cueva del; 3633 cave; 3634 shaft; 3635 sink; 3662 cave; 3702 dig;
S Vega 40 Comellantes, Cueva del; 48 Reñada, Cueva-Cubío de la; 333 Azpilicueta, Torca de; 1220 shaft; 1340 shaft; 3467 shafts; 3670 cave; 3671 shaft; 3672 shaft; 3673 shaft; 3674 shaft; 3675 shaft; 3676 shafts; 3677 shaft; 3678 cave; 3679 shaft; 3680 shaft;
San Antonio 3238 cave; 3283 Invisible Cave; 3629 dig; 3630 digs; 3657 shaft; 3658 shaft; 3659 shafts; 3660 shaft; 3661 caves; 3703 dig;
Secadura 3699 dig;
Seldesuto 258 Calleja Rebollo, Torcón de la; 570 shaft; 571 shaft; 572 shaft; 659 shaft; 3619 shaft; 3620 cave; 3621 shaft; 3625 shaft; 3626 shaft; 3627 shaft;

Summer expedition

   During a very dry summer, the main explorations occurred in Cueva Mostajo - where a passage was opened up at the end of the high level, dropping down to the middle level to head southeast towards Cueva Cofresnedo and Cueva del Sotarraña - and Lenny's Cave at Secadura, where good sized passage gives a tantalising glimpse of what may lie under the hill to the south of Secadura. A major addition to the summer expedition was the participation of 9 divers. Sites investigated included Cueva Comellantes, one of the Cueva Riaño resurgences, Torca la Vaca (through Cave of the Wild Mare), Surgencia de las Crecidas in Secadura and downstream in Cueva Llueva. A keen group from Manchester University Speleological Club were also an asset to the expedition.

Southern Sector
   Chris Jewell, diving in Cueva Comellantes (the main resurgence for caves under the southern La Vega hills - the South Vega System) with assistance from Laura Trowbridge, discovered the link upstream to Squirrel's Passage in Cubio de la Reñada. The latter had been last dived by Rupert Skorupka at Easter and the link was made when Rupert's line reel was discovered lying in a rock pocket. Rupert later investigated the resurgence looking for another source for the resurgence water, as the water in Squirrel's Passage cannot account for all the flow.
   Before the underwater link was made, teams on each side of a dig between Comellantes and Reñada had made voice contact and were excavating a tight connection.
   In Cueva Molino near Arredondo, Chris continued the dive started by him and Artur Koslowski last year. Using a rebreather in a dive lasting 6 hours 40 minutes to a depth of 93m, he found the cave closed in at -6m after adding 40m to the length. The main water flow has been missed somewhere in the 925m traversed from base.
   A small extension was made near Swirl Chamber in Cueva Vallina and, further into the cave, a Disto reading of 48m probably only went halfway up the Novadome aven.
   High above the possible connection between Vallina and the South Vega System, sites 1220 and 1340 were investigated. The first was explored down a p10 to an unexplored 3-ladder drop with a tight top. Site 1340 was explored to a choke at 27m depth.
   A small cave (site 2753), about 200m east of Torca de Reguilón, was enlarged at a constriction part way in, but the cave finished after 50m.
   In Ozana, small extensions were made in the often-visited Cueva de Jivero 2 and Anderal 2 (not explored since 1975). The latter was also found blocked by silt along the main route.
   In Cueva del Coverón, a new survey was started to better understand the relationship between middle level passages and possible connecting routes in Torca CEZ.

El Naso area west to Las Calzadillas
   The spacious high level in Torca del Mostajo heads northeast towards site 415 then appears to end in a boulder-floored chamber. Holes down just before the end were pushed in 1986 but not fully explored or surveyed. Another look this year took explorers through a tight section into "stompy passage" which heads southeast away from site 415 but towards, and on the same level as, the large and ancient passages in Cueva Cofresnedo and Cueva del Sotarraña. Near the end the "passage gets smaller but continues through into a chamber maybe 7m in diameter. Running out of time, we left a survey station with a note and surveyed out." There are "many leads left to check".
   On the opposite side of the Cubija Valley, Simas del Picón (another fragment at the same altitude as the higher level in Mostajo) was investigated in a couple of places. North of the Music Box, a 1m wide hading rift was descended to a small draughting hole which was disto'd down 50m. This appeared to link directly into passage in Torca del Regaton. The hole was enlarged but narrowed in again 15m down where it seemed that the disto distance had been a very (un)lucky shot. The second work site was in Mega Bat passage where the end was opened to allow access to the roof of a possibly 5m high chamber. This was later explored into a 6m diameter chamber with no exit, although there is a draughting window in a side chamber. This appears to be close to the Picón Pie area of Cueva de la Morenuca. One explorer sustained head injuries when boulders fell on him while descending a short pitch near the base. He was treated at the Ramales Health Centre with 4 stitches and a large dressing.
   More ancient human remains have been found in site 3153 and the permit authority, the Consejería de Educación, Cultura y Deporte, has been notified.

The Northeast Sector including the Four Valleys System
   An early push at the end of Cueva del Torno failed to find a route through to Cueva de Riaño. It is now probably best to have teams in both caves (with radios / radio location sets) if the 5 Valleys System is to be realised. Small surveyed extensions were made in Cueva de Riaño in the southeast extremity.
   A number of underwater explorations were made in the western resurgence (site 575) for some of the water in Cueva de Riaño. This site and a static pool 30m to the east were dived by Fred Winstanley in 1985 without success. This year, mostly in poor visibility, Dan Hibberts and John Taylor dived steeply down to -14m where the passage gently rises to -2m and continues. Over 200m were surveyed heading towards the downstream sump in Cueva de Riaño, now about 180m away. Progress was stopped by lack of time and very poor visibility in slow water flow. Site 1805, which lies over the top of the projected dive, was re-examined but there is little hope for any connection. Cueva de la Espada, the downstream sink for the water from Cueva de Riaño was dug at a muddy site which may reveal a separate streamway coming from the Llanío area. In Cueva-Cubío del Llanío, digging a draughting sand and calcite crawl at the eastern extremity has progressed a couple of metres.
   Three hundred metres northwest of Llanío, the awkward shaft 3451 was exavated down into (eventually) a stream passage with inlets. Over 140m were surveyed to a depth of 22m and there are possibilities for extensions.
  At the western end of the Fresnedo valley, site 2415 was re-examined but an inlet at the top of the 3rd pitch closed in after 15m. There is still a possibility for extending this site which lies over a probable water route to the Nacimiento del Campiazo.
   In the Four Valleys System, at downstream Cueva Llueva, Chris Jewell dived in poor visibility for 120m to -15m depth following one wall. (Phil Papard was the last to dive here in 1977 and 1995: in both dives visibility was very poor and the way on was not found.) Also in the Llueva valley, site 3691 was excavated in a number of places through a low crawl adding about 80m to the length. The work continues.
   The water in Cueva Llueva resurges at Los Boyones (site 117) about 1.5km away in the Secadura valley and it was near Los Boyones that a lot of time was spent in a number of caves. La Bodega (site 288) was re-examined and a new entrance found which gave a small amount of new passage with a complete, probably modern, pot about 25cm diameter across the widest point. The cave remains unsurveyed. Simon Cornhill dived in site 124, Surgencia de las Crecidas, finding an underwater continuation of the entrance passage and a boulder choke. Site 154, Cueva 77A was also re-explored and a passage pushed to the surface to create another 2 entrances.
   The main site found and explored in Secadura was number 3721, dug into from the surface through a constricted entrance series. The cave was explored over a number of days through large passage on a northwest-southeast line. Over 330m was surveyed with extensions probably taking the length to over 0.5km. A larger entrance was engineered when another passage approached the surface and both ends of the cave have possibilities for extension. The cave was named Lenny's Cave in memory and appreciation of Lenny Gee, a Derbyshire Caving Club member who had been part of the Matienzo Expeditions since the mid-seventies. He was particularly fond of digging and would have been delighted to have been involved in the excavation and exploration of site 3721.
   Slightly further up the hill from the previous sites, cave 289 was re-explored and excavated up into a higher level chamber where possibilities for extension stopped. A number of other small sites were documented in the Secadura area.
   In La Secada, the archaeological site 709 was revisited and a number of bones noted: possible articulated deer bone, burnt bones of cow and deer and a human finger bone.
   At a much higher level, on the hills to the east of the Matienzo depression, a number of sites were investigated, some to a conclusion! Site 730 was explored down a a p5 and p15 into a 30m diameter choked chamber. Site 811 was finally explored, 22 years after first documenting it. An 11m pitch dropped to an ascending passage and another 11m drop which choked. Cave 170 was surveyed along its 47m crawling length. The altitude puts it about 35m higher than the base of the nearby Torca de la Muela. Site 3504 (labelled "AA76" on the track on the north side of Muela) was explored down past a section enlarged by a supposed Spanish group to a choked chamber and then surveyed.

Northwest Sector
   Shafts seen high above and to the south of Cobadal at Easter were all quickly written off when 3681 was explored to 25m choked depth, 3682 to 6m depth and 3683 to 3m. To the northwest of Cobadal, the sumps in Dos Perros were looked at in dry weather but prospects remain "inconclusive".
   Colin Hayward and Jim Lister continued their campaign upstream through the sumps of Cave of the Wild Mare into Torca la Vaca. They passed through 5 sumps to dive the Upper Whitworth sump which led to a large chamber and a 51m dive through Elephant Sump to Lake Bassenthwaite. The divers believe that the water flowing in the Buttermere Series is not being fed from Lake Bassenthwaite and the best prospects are downstream Whitworth and the chamber at the start of the Elephant Sump.
   Torca de Luna de Miel, a possible top entrance to Torca la Vaca, was pushed but an alternative descent at the bottom was not enlarged or descended as parts of the hole started to disintegrate, defying a polyurethane foam solution. The very strongly draughting site 3719, 250m northeast of Honeymoon Pot, was opened up and descended. All leads in the 49m long, 12m deep hole either closed in or choked.
   Halfway between Torca la Vaca and La Gatuna, site 3048 was excavated on a couple of occasions reaching 2 low ways on which would require major engineering. A nearby draughting hole was opened up but the loose boulders here have been left to stabilise.
   At La Gatuna, on the hillside to the west of Cueva de Collada, sites 3714 - 3718 were documented. Site 3714 was the largest: an 8m pitch to a slope and choke.
   Hypocritical Hole, a small resurgence at the head of La Gatuna was pushed after the Spidery Duck was bailed and about 15m of very tight passage explored.
   At San Antonio, site 3703 was opened up into about 20m of maze cave.
   Site 3420 (Washing Machine Hole), at Ideopuerta, was re-excavated of silt and other washed-in debris. (This site will not be visited if there is any sign of rain.) Passage to the south was surveyed and a traverse over a couple of pits revealed a third which is estimated at 50m deep and has yet to be descended.
   Across the deep valley to the west, at Moncobe, the leads in the 1.6km El Cubillón system were not pursued but nearby site 3649, Cueva de la Casa Vieja, was opened up and explored. Pitches of 4m and 14m ended at a rift of boulders down to the head of a deep drop. This was initially thought to be about 130m deep but reality found the floor 85m down. A 5m climb up at the base reached a 20m drop and a low, muddy and obviously often flooded section. Of interest is the unexplored passage that goes off on both sides of this fine shaft, about 40m down.

   The list below shows links to those 131 sites which were extended or newly discovered over the summer 2012, or which have had surveys, references or descriptions updated, entrance photos or movie clips added, or entrances repositioned with a GPS.

Arredondo 733 Vallina, Cueva;
Bustablado 727 Molino, Cueva del;
Cobadal 2099 dig; 2988 Dos Perros; 3681 shaft; 3682 shaft; 3683 shafts; 3694 sink;
Coteron las Llanas 1360 shaft; 3739 dig; 3740 dig;
Cubija 71 Mostajo, Torca del; 75 Picón, Simas del; 76 Campo, Cuvia del; 892 Regaton, Torca del; 3722 cave; 3723 dig;
El Naso 59 Molino, Cueva del; 3559 cave; 3746 dig;
Fresnedo 2366 Torno, Cueva del; 2415 shaft;
Hornedo 767 Wild Mare, Cave of the; 2889 Vaca, Torca La; 3048 dig; 3594 Luna de Miel, Torca de; 3719 shaft; 3720 dig; 3737 dig; 3738 shaft;
Ideopuerta 3420 shaft;
La Colina 1023 cave; 1024 cave; 1025 cave; 3712 dig;
La Gatuna 2887 Hypocritical Hole; 3714 shaft; 3715 hole; 3716 shaft; 3717 hole; 3718 cave;
La Secada 146 Garma Redonda, La Cueva de; 261 shafts - 3; 708 cave; 709 cave; 723 cave; 1438 dig; 3700 resurgence & sink;
La Vega 3153 cave;
Llueva 114 Llueva, Cueva; 3691 cave; 3734 cave;
Moncobe 2538 Cubillón, El; 3648 shaft; 3649 Casa Vieja, Cueva de la; 3651 shaft; 3735 shaft; 3747 dig;
Muela 170 cave; 171 shaft; 489 Espino, Cueva del; 730 shaft; 745 cave; 811 shaft; 1397 shaft; 3252 holes; 3296 hole; 3504 cave; 3713 shaft; 3724 cave; 3725 shaft; 3726 cave; 3733 hole;
N Vega 3622 cave;
Ozana 2 Coverón, Cueva del; 9 Anderal 2, Cueva del; 17 Jivero 2, Cueva de; 24 Puerta, Cueva de la; 517 XLs, Torca; 1260 cave;
Riaño 103 Espada, Cueva de la; 105 Riaño, Cueva de; 107 Hoyuca, Cueva; 575 Resurgence Riaño; 1616 dig; 1618 dig; 1668 cave; 1669 cave; 1670 dig; 1789 sink; 1805 cave; 1809 cave; 2479 shaft; 3234 Llanío, Cueva-Cubío del; 3384 dig; 3451 shaft; 3662 cave; 3727 depression; 3730 sink; 3736 shaft; 3744 cave; 3745 shaft;
S Vega 40 Comellantes, Cueva del; 48 Reñada, Cueva-Cubío de la; 333 Azpilicueta, Torca de; 675 shaft; 1220 shaft; 1340 shaft;
San Antonio 3011 shaft; 3439 shaft; 3703 dig;
San Miguel 3280 Joe's Lost Cave;
Secadura 118 Churro, Cueva del; 124 Crecidas, Surgencia de las; 154 77A, Cueva; 288 Bodega, La; 289 cave; 631 Chica, Cueva; 2520 cave; 3721 Lenny's Cave; 3728 dig; 3729 cave; 3731 collapse; 3732 cave; 3741 hole; 3742 resurgence; 3743 cave;
Seldesuto 35 Arenal, Cueva del; 2753 cave; 3318 dig;


   The Matienzo caving expeditions share permission for the Voto (LLueva / Secadura) area with the Asociación Deportiva Espeleo y Montaña Colindres. In the 2011 feedback report to Cultura, ADEMCO write about explorations in previously documented (but unexplored) sites. In Llueva, site 3332 has been explored down a very tight entrance shaft to a choked depth of 10m. Explored to a depth of 4.5m, site 3062 has no possibility of continuing.
    A number of small new sites have been explored. In Llueva, Torca del Xsara, site 3748, is a blind 6m deep pot by the road side; site 3749 is also choked at 9m deep and site 3751 is "without interest". In Secadura, an interesting site is 3750, up a side valley 400m west of Torca del Rayo de Sol. Water sinks inside this 24m long cave at a wet, "impenetrable", strongly draughting crawl.
   ADEMCO also state that they haven't found any new passage in La Covarona or Torca de Simón 1.
   On a September visit to the entrance passages in Cueva Hoyuca, a team from AEC Lobetum (Cuenca) photographed a blue harvestman.
   There were Matienzo Caves expedition cavers exploring and digging over 4 weeks in October and November. One group was based in La Cavada and worked in the Ideopuerta / Moncobe areas. The other team concentrated on sites in the Matienzo depression.

Southern Sector
   A number of small finds were documented on the southern La Vega hillside (sites 3772 - 3775). The continuing shaft at site 1220 was revisited. A draughting slot was found near the base of the second pitch. A radon detector was left inside the entrance at Cueva-Cubío de la Reñada. The results can be seen here.

El Naso area west to Las Calzadillas
   In Simas del Picón, the old ASC Extension (first entered by French cavers) was re-bolted, re-explored and excavated into a new chamber - Melted Wax Candle of Doom Chamber. A traverse around the pit opposite the bolt climb now bypasses the bolt climb through an excavated drop. A couple of days were spent in the Lastrillas area finding a number of minor sites, 3763 - 3769.

The Northeast Sector including the Four Valleys System
   A radon detector was left in the High Hopes chamber in Cueva-Cubío del Llanío. The results can be seen here. Behind Lenny's Cave, site 3777 was discovered and dug in a bedding with a slight draught. In the nearby site 3778, a crawl ends at an undescended drop.

Northwest Sector
   At Moncobe, El Cubillón was entered once and a climb to a pretty grotto pushed. Extensions in Cueva de la Casa Vieja include a very tight crawl to another big drop and a short length of new passage after a p5 at the base of the p14. A 40m bolt climb down the p85 has confirmed that the holes in the shaft wall appear to "go". More bolting will follow. A number of sites were dug to a conclusion: three digs were completed in the amphitheatre area. Other digs are continuing, eg site 3692 where the depth is currently 7.4m. At site 3758, the cave could only be entered after a wasps' nest had been cleared out.
   Near Ideopuerta, the entrance crawl in Washing Machine Hole was found to be sumped. Above, 2 small, linked caves were explored, site 3779. Digs were also a major part of the activity in this area. Site 3752, for example, has some promise as does site 3756 with a good inward draught.
   More digging was carried out at site 3215, above the Duck Pond sink.

   The front cover of Descent, issue 229 has a 'definitive' photo of the Astradome by Paul 'Footleg' Fretwell and, inside, Paul explains how the photo was taken and processed.

   The list below shows links to those 56 sites which were extended or newly discovered over the autumn 2012, or which have had surveys, references or descriptions updated, entrance photos or movie clips added, or entrances repositioned with a GPS.

Camposdelante 3215 dig;
75 Picón, Simas del; 2167 Frank's Cave; 3129 Symmetry Pot;
3420 Washing Machine Hole; 3752 digs-3; 3753 shaft; 3754 cave; 3755 shaft; 3756 cave; 3757 cave; 3779 caves-2;
3763 cave; 3764 dig; 3765 dig; 3766 cave; 3767 dig; 3768 dig; 3769 dig;
112 Covarona, La; 3062 Traviesas, Torca de las; 3332 Bendito Pantin, Torca; 3748 Xsara, Torca del; 3749 Lápida, Torca de la; 3751 cave;
2538 Cubillón, El; 3615 cave; 3616 cave; 3649 Casa Vieja, Cueva de la; 3650 caves; 3669 caves; 3692 dig; 3693 cave; 3747 dig; 3758 cave;
N Vega
443 shaft; 2661 cave; 3632 dig; 3709 dig; 3770 dig; 3771 dig;
107 Hoyuca, Cueva; 3234 Llanío, Cueva-Cubío del;
Riva 3603 CEZ, Torca;
S Vega
48 Reñada, Cueva-Cubío de la; 1220 shaft; 3772 shaft; 3773 shaft; 3774 shaft; 3775 shaft;
121 Simón 1, Torca de; 3721 Lenny's Cave; 3750 Jabalí, Cueva del; 3776 dig; 3777 Dos Burros; 3778 cave;

Christmas & New Year

   The explorations over the Christmas/New Year period were mainly digging out then exploring, but not very far. Over 30 sites were investigated including 10 new holes.
South of La Secada
   The entrances, lengths and depths for the South Vega System were rationalised hence the 8 entries below. In Sima-Cueva del Risco an impressive sediment bank was photographed.

The Northeast Sector including the Four Valleys System
   A couple of days were spent on the Llueva-Secadura ridge where a number of small holes were investigated. Site 1985 and 1986 were opened up but the biggest find was the excavation and exploration of a 15m shaft, site 3785.
   In Secadura, a useful surface survey and more GPS work positioned more precisely (and accurately?) the entrances to a number of caves. Of these, site 3741 was dug down for 4m to a draughting, narrow slot about 40m away and 9m above the western end of Lenny's Cave. In Lenny's Cave, site 3721, surveying in the eastern part of the cave took the length of passage to 477m with a vertical range of 16m. The position of La Bodega was also improved so that water in Lenny's can make a straight line exit to the resurgence. La Bodega was also partly surveyed and appears on an area map, along with 3741, Lenny's Cave and the surface survey track.
   Another site of interest was 3778 with a 7m pitch.

Northwest Sector
   Most time was spent in the northwest sector, around and to the south of San Antonio / La Gatuna.
   High above Suit Wrecker Inlet in Torca la Vaca, some digging was carried out in site 3069 and 3786 and sites 2717, 2725 and 2726 were investigated. A number of sites were looked at to the north of Torca de Peña Encaramada: site 3524 proved to be a vertical "rabbit hole" and site 3780, three short holes overlooking the road. Site 3784 was found to be a short pitch into a low chamber with an almost complete horse skeleton and other bones.
   In La Gatuna, site 2317, first seen in 2005 with an impressive capping bed of sandstone, was excavated of sand at the base of the entrance. A rift passage was entered with no clear way on. Site 2369 was explored for 10m in a well decorated passage. A new cave, site 3781, was found below a sandstone bed and explored for about 20m in a series of tight cross rifts.

   The list below shows links to those 42 sites which were extended or newly discovered over the Christmas 2012 and the new year, or which have had surveys, references or descriptions updated, entrance photos or movie clips added, or entrances repositioned with a GPS.

Barrio de Los Urros 3069 shaft; 3786 dig;
3524 shaft;
La Collada 2717 shaft; 2725 shaft; 2726 shaft;
La Gatuna
2317 cave; 2319 shaft; 2326 shaft; 2328 shaft; 2369 cave; 3781 cave;
1707 shaft; 1985 shaft; 1986 cave; 3782 cave; 3783 dig; 3785 shaft;
Llueva/Secadura 891 Verdura, Cueva;
25 Risco, Sima-Cueva del;
S Vega 36 Vera Negra, Torca de la; 40 Comellantes, Cueva del; 48 Reñada, Cueva-Cubío de la; 264 Coterón, Torca del; 333 Azpilicueta, Torca de; 675 shaft; 1338 shaft; 1471 Papá Noel, Torca de;
San Antonio 3089 shaft; 3090 cave; 3661 caves; 3780 holes-3; 3784 shaft; 3788 dig; 3789 dig;
Secadura 288 Bodega, La; 3547 dig; 3721 Lenny's Cave; 3741 dig; 3778 cave; 3787 shaft;

Juan Corrin, 2012. January 2013