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Tresviso Caves Project 2019 *Caves and Mines! -- rope sponsorship entry


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At the start of September last year, I was being driven up the mountain roads leading through Las Arenas to Sotres and beyond to our home for two weeks; Tresviso.  Eyes wide open at the amazing sites on-route, the large valleys bearing a small resemblance to Winnats Pass, the springs at gas stations where locals and tourists fill up water bottles with pure mountain water and the numerous zig-zag mountain roads.


(The Marniosa and Agua systems overlaid on terrain)

We return this year, sadly without the blue team of ?SUSS? perched on the hills above, under the banner of the Tresviso Caves Project, but most definitely trying to fly the SUSS flag when the National Park wardens weren?t watching.  Thankfully for them this was possible in the second week when they were in glorious sunshine and us townies had low lying clag for a couple of days.
At least two of the blue team are joining us down in Tresviso this year which will be great.

This year we hope to expand on the recent efforts of explorers in the region, already a crack team have been out early to continue the electronic resurvey of upstream Cueva de la Marniosa and to do some quick surface bashing for promising leads.

This expedition is mainly focussed on the two systems of Cueva del Nacimiento (or Cueva del Agua for the 70?s & 80?s readers) and Cueva de la Marniosa which represent the 1st and 3rd longest systems within the expedition area. 


Cueva del Nacimiento (Agua)

There are some fantastic leads at the back end of Agua (the most southernly point in the system), including 2 avens to climb in ?Pina Colada Bypass? (below the Death Race chamber, at stream level) and ?Joe?s Crack? (just off Death race chamber), a drafting squeeze to enlarge at the ?Wet Aven? in ?Teeth of Satan? and also ?The Sandy Dig? in Jurassic World (south westerly lead).

Two leads in Agua are also on the list but are more of a modest distance into Agua, are to explore a maze section in the vicinity of ?Dan?s Big Room? and ?Winter Gardens?.  A dive of the ?Parting Friends? sump is also planned, which the divers are hoping to push in the direction of Marniosa, to hopefully find dry passage beyond, some dry cave in this area would be a wonderful thing for dry cavers on the surface to aim at.

South of the current extent of Agua sit some of the deepest caves, they lie right on top of the biggest mountains in the Eastern Massiff, including Torca Jou Sin Tierre (-1203m) and Sima 56 (-1169m).  Any connection between these caves and Nacimiento would create a >1600m through trip.


This .3D model shows the deep caves on the left (or South), with the Agua System on the middle right and Marniosa on the far right (North). The view is taken from an angle below Tresviso looking up valley at the systems. There is a huge amount of Passage to discover between the left and right of the image.

Cueva de la Marniosa

The British connection with the Tresviso area is longstanding and arguably the legend of LUSS lives on strongest in the Marniosa system.  Marniosa was first explored in the early 1970?s and is believed to be a feeder into Nacimiento.  Recent exploration of the cave has pushed it to within 350m of Nacimiento.  If joined together the combined system would be over 20km long and offer multiple through trip options.

Last year, following up an obscure 1979 LUSS lead a surface site was pushed to find T20 Silvestre, all the way down to some telling LUSS graffiti marked in carbide, the upstream of Marniosa.  The first ever through trip will be attempted this year.  If this is done then a further objective in upstream Marniosa and SIlvestre will come into play, which is to find further upstream leads heading toward the Valdelafuente.

The Valdelafuente lies to the south of Marniosa. Pushing towards and beyond the Valdelafuente, has the potential to push the Marniosa system further west than the western reaches of Agua and into unknown territory.


Keen eyes that were behind the camera will know that the bottom right photo is actually of ?Here?s what you could have won? in Agua. The Top right is of the Silvestre entrance and left image is of the LUSS Graffiti at the end of Marniosa (/last years connecting point of T20 Silvestre)

Secondary Objectives and Surface Prospecting
With a reduced team size, the main objectives could prove enough to keep us busy, but there will be a few cropping up onto the board should the clag descend on the valley again. Two Ridge and surface bashing objectives hope to connect into either Marniosa or Agua and more work on the Minas de Mazarrasa area.
Secondary objectives: Mines
It was the Minas de Mazarrasa project which Hannah and Chris used to lure me to join last year, when they were showing me photos of a rotting piece of timber while supping our pints in the Cheshire Cheese. The Minas de Mazarrasa region is covered in old mine workings and natural shafts, the whole effect is that of the Coniston Copper Mines, but on steroids (and not copper mining).  Lots of open pits and a few adits which connect back into the system, give the place a friendly feel for the mine explorer, despite the long walk up the hill.
Secondary objectives: Caves
A surface walk of various wooded sections of the Sierra del a Corta and further pushing of various sites may well provide significant gains towards the ?Terror Firma? and ?Jurassic World? passages in Agua.  This would vastly reduce the pushing time for future objectives of the expedition.
Further prospecting around the Valdediezma area will look to drop into an 80m aven in the downstream section of Marniosa beyond sump 1.

I could wax lyrical about all the different leads around Tresviso, there being dozens of leads in each system and hundreds of caves and systems to explore. But we?ll not get through all of the leads, and will likely have to come back for quite a few years before the Tresviso region gives up it?s biggest secrets.
We will use the rope in Silvestre if Sir Phil doesn?t try hiding it behind the crate of beer in his car, not that we?ve been stopped before.

And of course we will be exploring la caberna. Sorry, la taberna...



Well-known member
Again, I've been bending the truth, The photo is not of a bar in the town of Tresviso, but of Anna's in Sotres.

However, I believe this could have been the place where most of you guys went when you were there. I've heard that the road to the town of Tresviso was mostly a track until EU funding helped us cavers out!


Active member
We did go to a bar in Sotres. Had Sweetbreads hanging off the ceiling... :LOL:

And the road was indeed an unmade cart-track.  ;)

It's a smashing part of the world. Negotiable by motorbike now I guess....lol


Well-known member
Still negotiable by cattle mind! Given the herd we kept encountering on the road, especially on the last night when we had 15mins for a ?pitstop? Shower and stockup on a crate of beer before the meal.


The 2019 expedition is only a few weeks away. Hopefully some interesting blog posts will be created, but firstly, as per previous years, a bit of a brief overview of expedition:

Overview & brief history:
The Picos de Europa is a range of mountains 20km inland from the northern coast of Spain, forming a westerly extension of the Cantabrian Mountains. It consists of three main areas, the Western, Central and Eastern Massifs.


Picture: Andara (Eastern Massif) viewed from Tresadura (looking South) (Phil Walker)

  • The Western Massif is to the west of the Rio Cares and has been explored by a selection of clubs including Oxford University Caving Club (OUCC), Seccion de Espeleologia Ingenieros Industriales (SEII), York University Cave and Pothole Club (YUCPC), Sociedad de Espeleologia Geologicas (SEG) and Speleo Club de Paris (SCP). This now includes the area under exploration as part of the Ario Caves Project.
  • The Central Massif is between the Cares Gorge and the Rio Duje and has been mainly explored by the Speleo Club de Seine (SCS).
  • The Eastern Massif is to the East of the Rio Duje. Lancaster University Speleological Society (LUSS) were exploring the Eastern Massif from the early seventies to 1987 with the help of SEII.

It was the Eastern Massif (or Andara) that drew the attention of LUSS in the early 1970s. In the early years exploration was mounted from the mountain village of Tresviso and exploration was dominated by the resurgence cave Cueva del Nacimiento (Cueva del Agua) located at the foot of the mountain range. The resurgence flows into a canal that contours the Urdon gorge with an average flow of 2 m3/s and the cave behind the resurgence leads to >12 km of surveyed passage and a height gain of over +534m.

The catchment is some 40 km3 and includes caves such as Torca Jou Sin Tierre (CS-9) at -1203m deep and Torca del Cueto de Los Senderos (Sima 56) at -1169m deep.

In the late 70?s LUSS pushed Cueva del Nacimiento to around the 11km and +300m mark, but after several years the cave was abandoned as all the major routes sumped and no continuation could be found. LUSS then turned their attention to the Andara region higher up the mountain range and sought caves that would drop into the Nacimiento system and hopefully create a record-breaking >1500m traverse. They found a number of deep caves around this ?top camp? area; Sara, Tere, Flowerpot, Dosser?s Delight and Sima 56 were all pushed to respectable depths but a
connection remained elusive.

The discovery of newer and deeper systems, plus improved GPS, have changed the figures slightly but a connection between the deep potholes and resurgence would create; a cave in the top 10 worlds? deepest, deepest in Spain and potentially one of the the deepest underground traverses in the world.

Top EntranceAreaAlt(m)Current Depth(m)Vertical Range(m)
S-33 Torca de la HendidaSamelar2100-4521620
CS-9 Torca Jou Sin TierreCueto Senderos2074-12031594
Sima 56 Cueto de Los SenderosCueto Senderos1975-11691495
T82 Karen ? 2.6 Sara Grajal (Sara depression)1880-5911400
T145 ? Pozo CastilloMazarassa1870-3091390
2.24 TereGrajal (Sara depression)1820-7921340
FT39 CompromissoMazarassa1820-3131340
T169 FlowerpotPico Boro1785-7231305
T173 Dossers DelightPico Boro1706-8311226
T190 SeptrinPico Boro1696-1801216
3.2 Torca Branarredonda (Fallen Bear)Samelar1589-4561109
T510 Cueva Entre CuetosSierra del a Corta1305-117825
T69 ? Pozo MotillaSierra del a Corta1248-70768

Note: There are at > 70 sites at higher altitude than CS-9 that would surpass -1600m deep through trip, with some close to -1800m depth.


Picture: Pena Colada Sump (Cueva del Nacmiento) (Rob Middleton)

Expedition Dates
  • 31 st August 2019 to 14th September 2019 ? main expedition dates

The expedition has several goals. The following are a few primary objectives:

Cueva del Nacimiento

  • Jurassic World ? The Sandy dig, draughting lead, now only an hour from camp
  • JPina Colada Bypass ? calcite aven to climb
  • JJoe?s Crack ? continuing shaft behind Death Race camp.
  • JTeeth of Satan ? Wet Aven ? +30m aven with draft and calcite squeeze, requires enlarging.
  • JDan?s Big Room ? unexplored section of maze in area of Dan?s Big Room, Peanut Chamber and Winter Gardens
  • JParting Friends ? a dive of the Parting Friends sump is planned.

Cueva de la Marniosa

  • Beyond Sump 2 ? undescended 6m pitch
  • T20A Silvestre ? Marniosa ? first through trip to be completed
  • T20A Silvestre ? upstream leads, heading toward the Valdelafuente


Picture: Downstream Marniosa (Joe Daniels)

Secondary Objectives:
Time and resources permitting there are several secondary objectives that will be attempted:

Sistema Castillo
A large mine and natural cave complex in the Minas de Mazarrasa area. Pozo del Castillo series was explored to ? 292m depth in 1983, with either a howling draft or roaring waterfall beyond a constriction at the limit. The potential of the cave is significant but currently a collapse prevents getting to the end. Pozo Natacha series ends at -309m depth and is close to the same point in Castillo.

  • Pozo Del Castillo ? shoring and bypass of rock collapse Castillo remains a major lead, if we can get past the blockage! In 2018 the snow level had dropped and possible to get into the next section.
  • Pozo del Castillo ? other entrances. FT16 entrance snow plug would appear to be the same blockage in lower Castillo passage. Snow plugs are reported further into the cave, so another entrance must exist!
  • Pozo del Castillo ? surveying of Natacha upper series and locating possible surface entrance,

Valdelafuente / Sobra Valley

  • Re-locate draughting surface entrance on Valdelafuente, close to 80m aven beyond Sump 1 in Cueva del Marniosa,
  • Yorkshire Inlet in Cueva del Marniosa. Exploration of col above aven

Sierra del a Corta

Above the furthest reaches in Nacimiento is the Sierra del Corta. A heavily wooded area with a number of promising leads, that could potentially drop into Nacimiento and provide an easier route into the back-end to aid exploration at the far reaches.

  • T554 ? large 100m shaft on the Sierra del a Corta, this requires some digging at the bottom,
  • Al2 ? a drafting shaft not yet bottomed. Jurassic World in Nacimiento appears to be heading directly towards this site,
  • T294 Oh What Pot (La Gobia) ? continuing passage,
  • Surface prospecting close to vicinity of Terror Firma in Nacimiento. Terror Firma is only 40m vertically and 200m horizontally from some parts of the surface in the Sierra del a Corta region.


  • Locate and descend FT43, this draughts strongly. It is almost directly above Boulder Chamber in T87 Mazarrasa and would provide bypass to collapse at T87 entrance.
  • Prospecting on Hoyo Oscuro and Hoyo Evangalista. Highest entrances on the mountain range.
  • Mine 2.32a ? there is large unexplored level (with tram lines) leading to unexplored passage.


Picture: M6 Toll Bypass, Cueva del Nacimiento (Arwel Roberts)


The times they are a changing (by Howard Jones)

Brief history
In the 1970?s LUSS were caving in Northern Spain, inland from Santander. They learned about a village where cheese was made and matured in caves. Nearby a resurgence cave fed a hydroelectricity scheme. Add in some high mountains in the vicinity and it was Xmas for cave explorers. Tresviso was first visited in 1974 and cavers from LUSS and other clubs, both UK and foreign, have been visiting ever since. The resurgence cave (Agua ) has been surveyed in excess of 15km and Sima 56 was pushed to a depth of -1169m. Vertically they have over lapped, horizontally they are 4km apart. If joined they would establish a world class system, and maybe a through trip!

The Village
Tresviso is a lovely village of some 25 houses sat at the top of the Urdon gorge. The families used to be subsistence farmers living off the proceeds of goats and cheese. When we first arrived in vast numbers and camped just outside the village, we must have swamped their existence. Yet we were absorbed into their company without rancour and have been so ever since.

When the track from Sotres was improved to a road village life changed and nowadays many villagers leave in the winter a return in the summer. There are far more visitors than before and life in the village has changed for ever.

In the 70?s there were two ways to Tresviso. A track came in from the village of Sotres some 10k away which could usually be passed by a land rover, though was sometimes blocked by rock fall. The other way in was up from the Urdon gorge, a 6k march with 900m of ascent. The bus from Santander would drop us at the bottom and the nightmare ascent would begin. For many of us this was our introduction to Tresviso expeditions and it was brutal, staggering up this donkey track in the mid-day heat with your caving gear on your back. As a way of making you cave fit it was ideal. Hopefully the expedition land rover had made its way in via Sotres and you could unpack your tent, home for the next 9 weeks.

10 years ago, the track from Sotres was engineered into a metalled road and saloon cars can now drive to Tresviso. This has changed a lot of aspects of Tresviso life, not least cavers can drive to Tresviso and no longer sweat up the track!

In the 70? we would camp in a field just above the village in a sloping field which had been harvested early. Water was gained from a trough and flies were a problem. A big communal cooking tent was used to store food, you slept in your own. Life was pretty basic and there was little incentive to hang around camp all day. Evenings were spent in the bar, a red wine often lasting all evening for an impoverished student.

Nowadays we stay in a hostel in the village. Bunk beds, electricity, hot water, an oven all make life a lot more comfortable. A store room downstairs is used to leave gear in from year to year which makes logistics much easier. Some things have not changed though, evenings are still spent in the bar.

Caving in the 70?s meant wet suits, carbides (stinkies) and texolex helmets was all we knew. Over suits were proofed cotton which ripped to bits in rifts, under suits bought second hand from the air force which for some reason had short arms and legs. Harnesses were homemade or the dreaded Whillans which rearranged genetalia. In short caving gear was a mixture of home made or adapted from other uses.

Petzl changed all that and LED and battery technology has made life underground much safer and pleasant. Cave photography and surveying can now be undertaken for hours without the risk of imminent exposure, with better results to boot.

Snow fall has decreased remarkably over the 40 years. The days of digging out the White house door and cave and mine entrances are largely gone. In May 2019 there was little snow at Andara (top camp area) and by September there was none. A few shafts are still snow plugged, but this must be yearlong. The river caves of Agua and Marnioasa are thus drier and safer and the tracks and roads keep in better condition.
Cave names
One of the joys of exploring caves is you get to name them and the passages within. In the 70?s Bob Dylan songs were popular and a quick glance at the Agua survey proves this to be the case. As time moved on other influences have been reflected.
I was always surprised that the Spanish caving authorities allowed us ( and other foreigners) to come and explore their prime areas, surely in years to come the next generation would be appalled that so many of the world class Spanish caves had been explored by non-Spanish teams, and yet despite changes to the permission rules we are still allowed to keep control of ?our area? 40 years on.

However, the Spanish cavers have got their own back by renaming our caves! The Cueva del Agua is now Nacimiento, which is very confusing to us old timers.


Cueva de la Marniosa

In the early 1970?s a group of students from Lancaster University Speleological Society (LUSS) touring Northern Spain heard about some caves near Tresviso, Eastern Picos de Europa.  In 1975, their first year visiting caves of Tresviso, they explored upstream, into the Sobra valley and found a crack in the side of a cliff that is Cueva de Marniosa.  They explored this cave down a few pitches and along some well decorated fossil passage to a high rifty passage with a small streamway in the bottom. Over a kilometre upstream, the streamway ends at the impressive Hall of the Mountain King chamber- a 50 m x 20 m chamber with a height of over 50 m.  The whole cave has a length of 5 km and a depth of 290 m.  Over the next 40 years a few extra bits were added, but other caves in the area were more interesting.

During the summer expedition of 2018 a small group were tasked with surface prospecting in the brambles, bracken and beech at the head of the Sobra valley and found a number of surface shafts. One of the surface shafts, Cueva del la Silvestre, descended a series of pitches to an impressive large 45 m deep, 20 m diameter shaft.  From the bottom of this shaft several ways on were found.  A few days later, on the final day of the expedition, more pitches and climbs were descended and a message from the past was found: LUSS.  A short walk upstream and the explorers entered Hall of the Mountain King.  Much to the chagrin of those involved the 500 m deep traverse of Silvestre to Marniosa would have to wait until next year?

Cueva de la Silvestre to Cueva de la Marniosa through trip (Lydia Leather)

We got to the Silvestre layby at about 11am, kitted up and started walking down the track. This time round it was a lot easier to find having been well travelled. Stu?s white tape on silver birch trees was not so great in the day light as it had been the night before. Whilst we were doing the through trip, Joe and Rob where diving the sumps in Wet Willy and had stolen Alastair for the day to carry for them. As Stu and I weren?t carrying much we took two of their bags down for them (on the basis that Rob would later repay us with a create of beer, but failing that, dancing bear coffee liquor).


The Silvestre entrance had been rigged the day before down to waterfall chamber, where Bob needed to re-bolt before we continued on with the through trip, so Bob and Arwel headed in whilst the rest of us followed behind. The day before Stu had found the jaw of what we think is horse, to match the skull he?d found the year before. Now Bingo (see photo for scale) lives happily in the entrance chamber.


Following through the rest of the cave, Rob who hadn?t been in the cave before grew increasingly more impressed at the fact that it was indeed a cave. We took our time marvelling at the finest bolder I?ve ever seen that sat in the middle of the stream way and is a conglomerate, at first I assumed it was originally the floor of the streamway and had been eroded away, but not all that convinced, think it might just be a boulder.


When we reached Bob an Arwel, there was a short wait for the bolting to be finished before we could reach the bottom of waterfall pitch 
When everyone was down waterfall pitch we left the diving team and their bags and continued on. From waterfall chamber we continued up the aided climb and through into old stream way rift passage. This continued on (picture below), getting slightly small in places (for Bob and Stu) and down climbs and eventully leads to a junction, left being the way on and right being Hall of the MountainKing.


As Stu and I hadn?t been before we went to Hall of the Mountain King which is an aven roughly 50m in height and 20m width, with a mud slope to the left of the chamber and 2 water inlets coming in through the aven above to the right. Here was where we stopped to take a group photo.



From Hall of the Mountain King back to the Silvestre junction we followed the stream and continued down the active passage way. The passage follows onward with multiple down climbs, some more exposed than others. Eventually the passage follows a fault and here the bolder choke began. Alastair Gott had been in Marniosa the day before and placed reflectors along the bolder choke which were extremely helpful and saved a lot of time as there are multiple ways along the choke in which you can go wrong. When the choke ends, the passage re-joins into stream way and this follows straight towards the bottom pitch of Marniosa

We headed up the muddy pitch out of the streamway, where Bob showed us ?the boulder? which must not be touched or moved in anyway as it was wedged right between the wall and multiple boulders which became the false floor of the next slope.
Following this onwards the passage is very well decorated series of chambers (see photos), with various calcite flow slopes and formations, including this flying pizza like disc thing... Eventually reaching the bottom of a 22 m pitch. From here there?s 3 more small pitches until eventually you get into the old cheese chamber and we were at the Marniosa entrance. The trip in total took 6 hours and we got out with plenty of time to spend in the bar drinking celebratory beers and eating local cheese. Rob and Joe eventually turned up and kept the promise of buying Stu and I a dancing bear coffee liquor.






Well-known member
On the throughtrip I did last Friday, I helped complete some the missing section of centreline (and survey) of the throughtrip from silvestre to marniosa, from the junction with hall of the mountain king down to a drop above water. We therefore had another short section missing. This short section included an interesting corner of the streamway.

I was intrigued by a black space above the streamway at this junction and also above the final survey point.

Me and Phil walker returned on Monday. The resurvey went well, 200m+ of passage was added to the centreline through the main passage.

When we reached survey point 42 we decided to investigate.

I popped over a boulder and wandered down a passage in a southerly direction (The 42 streamway) at this point Phil pokes his light into the black space above and found a large chamber approx 50m long, 30m wide and 15m high (alien weaponry). 2 further leads off alien weaponry are an aven (ted aven) and also a high level lead (District 9).

Arwel and bob we?re deployed today after a monster flood and were able to traverse back upstream to alien weaponry. They had to combat a large pond before getting to papoose pitch. And they report that going upstream was ?interesting? some further surveying of district 9 has added some length.

2 days left and Rob has promised me a cider if I survey and explore 250m tomorrrow.

Leo and me are pushing tomorrow.


The Tresviso expedition returned back to the UK last week and the following is a brief summary:

Cueva del Nacimiento - Parting Friends
In the entrance series of Nacimiento is an area called the Road to Wigan Pier and at the end if a waterfall climb to the Parting Friends sump.  This was originally discovered in the late 80?s and later dived by Gavin Newman / Phil Short, during the filming of ?Extreme Lives ? Road to Certain Death?.  Unfortunately, no survey exists, but the sump was described as around 150m, still continuing and, unlike a lot of the other sumps in Nacimiento, was not at depth.

It took nearly 4 days to rig the stream ready for the dive.  The grade 2 survey of the approaching passage proved to be misleading? 9m up pitches, were actually preceded by 60m of steep ramps, aid traverses and bolt climbs, all while stood next to (or under) a raging torrent of water. 

Eventually, all was set up and the divers, Rob Middleton and Joe Daniels, could attack the sump.

Dive 1 ? passed after 25m (at -6m depth) to 30m of streamway and climbs.  Second sump, 4m diameter passage, 115m line laid
Dive 2 ? sump 2 to -165m
Dive 3 ? way on found, passing believed previous limit to large airbell.  Sump continues in typical Nacimiento ramp style passage to another large airbell.  Fourth sump found and way on in open sump passage.


Total length of passage 439m.

The day after the final dive, the rain came in and flooded us out of the cave for 3 days.  A lot of equipment lost and the crucial dinghy to get across the entrance lake washed away, probably now wrapped round a turbine at the hydro-electric plant.

Cueva de la Marniosa ? Free Willy
In the upper series of Marniosa, before the streamway is encountered, is a section of cave called Extra Caverns.  Discovered in the late 70?s a number of leads and unclimbed avens exist.  Phil and Howard attacked the avens over a number of trips.  At the very far end, two small 5m avens lead to the same connection at the top (subsequently bypassed without the need for any climbing) leading to a tight rift and a draughting immature streamway.  2 further avens  (approx.. 10m) were found at the end but not attempted. 

Further back in the main passage, an obvious wet aven was scaled for 10m to where it split into 3 further ?avens?.  The left hand route led up for a further 20m to a narrowing rift, with limited potential.  The first right hand route led, after another 5m, to a tight upwards squeeze, passed by Leo to around 5m of passage and another 15m aven.  The final route from the junction leads back out of the main aven, but was only scaled for another 2-3m in poor rock, before time ran out.  This remains the most promising lead, with an obvious lip a further 5m up.

Cueva del la Marniosa ? new discoveries
On a final surveying trip, Phil and Alastair ?stumbled? upon two exciting new discoveries in the upstream Marniosa streamway.  Although not shown in the 70?s survey an obvious bend in the streamway has a dark space above.  A 3m climb up lead to a huge new chamber, 50m x 20m x 20m, with a large 35m aven at one end and a high level route at the other. 

Just at the bottom of the same climb up to the chamber, was a large boulder hiding a second streamway / inlet, entering the main stream.  This was pushed for around 50m and still continues.  The high level route in the chamber was revisited and extended for another 50m in large passage to a ramp down, probably into the same new streamway.

Silvestre Pot ? Marniosa ? First through trip
The first through trip from Silvestre Pot to Marniosa was complete by 2 teams during the expedition, before the Silvestre section was derigged ? see early post for a write up.

Silvestre Pot ? Sumps
Two sumps in the upper levels of Silvestre were dived.  Bob?s Crusade sump was dived for 32m (-6m depth) to an airbell, tight continuation possible but not appealing.  The Wet Willy sump was passed after 3m to a second sump aftetr 40m of passage.  Sump 2 is largely ?organic? and was abandoned after 2m.




Well-known member
A little teaser, I've got a little tidying up to do on this elevation I think!?!  :blink:


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Well-known member
Oh yes meanderthal, I've got a plan of the bit you surveyed  :sneaky: :tease: or theres the full copy so far on the reg. I need to tidy up the joins and buff it up a bit as I can't be publishing mess like the district9/42streamway elevation on an open forum  :spank: :blink:

Reg is here: http://cave-registry.org.uk/svn/Andara/Tresviso/Marniosa/therion/
use tortoise SVN and run the config . I think you should be able to export a copy of the full set of files. but we've been updating most nights, so it constantly changes.

Can send you a copy of the plan via email after the weekend, as I might have some time to tidy up over the weekend but no promises  :coffee: :beer: :alien: :halo:


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Well I wouldn't say it was "Done" but then where do you draw the line  :confused:

3 areas of interest (for me and others) for next year.
1) The 42 streamway which has essentially undermined District 9 and Alien Weaponry in the past and made them both the size they are. (this is approximately half way "upstream") This could potentially link back to "Your Mothers Gott a Penis" sump extensions.
2) Ted Aven, a promising aven in the North Eastern side of the roof of Alien weaponry.
3) The area before the downstream sump 1, including any caves on the surface. These could provide a bypass for dry cavers, but then I've never been downstream yet (so can't say for certain either way).


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