Tresviso Caves Project

Tresviso Caves Project Gazetter

T13: Cueva del Nacimiento

(Cueva del Agua, Cueva del Nacimiento de Urdon, Bardina del Nacimiento, Cueva de Reninuevo)

East, North:363921, 4789684 (nearby)
Coordinate Quality:GPS
Long, Lat:-4.6762427792057, 43.247653714159 (map)
Elevation (m):470
Length (m):18017
Depth (m):536
Active Lead:
Survey Available:


100m West of Tresviso, on the Sotres track, is a path leading down to the valley floor.
Following this route for 500m reaches the Urdon River.
The Agua entrance is behind an obvious dam and canal on the opposite side of the valley.
Entrance to Nacimento


Main entrance is the obvious passage across and to the left of the canal.
An upper entrance is located approx. 20m to the left of the main entrance and approx. 15m above. This entrance is usually sumped in all but the driest summers
Crossing the entrance pool


Due to the complexity of the cave only the major passages have been described. Many of the minor passages have been omitted, for clarity. Italics section detail minor passages of interest, but are not on the main route toward the back end of the cave.

Entrance to the Black Hole

The entrance swim, depending on water levels, is a cold 5m swim toward the obvious passage on the left hand side. A 2m climb out of the water, leads to a 2m wide by 1.5m high passage. The passage continues, in similar dimensions, over a number of dry pot holes in the floor, until the head of an obvious cross passage / chamber is reached. A 5m climb down, best life lined, leads into the start of a passage, trending upwards. A number of crawls / scrambles can be followed but all eventually meeting near the main stream way, by a large rock to one side of the stream. It is possible to cross here, at the top of a downstream waterfall, but a traverse line should be considered, in case of rising stream levels. Downstream can be accessed either via a bold climb down the waterfall (in low water) or via further crawls near the previous 5m climb down. The downstream passage eventually sumps and reappears in the entrance pool.

Crossing the stream, at the head of the waterfall, allows a traverse around the left hand side of the stream. Bolts have been installed along the side of the stream to allows a traverse line in high water. Following the water upstream for approx.. 20m leads to a short awkward climb. After a further 5m an obvious low crawl, at head height, on the left is the start of the 'New Bypass', the easiest route out of the stream and into the main cave.

Continuing upstream, the stream becomes more powerful before an upstream sump is encountered. Just before the upstream sump another low crawl, on the left, leads to an extensive maze of crawls and squeezes, which eventually connects back up with main cave close to the Black Hole.
The New Bypass starts as a low flat out crawl, ascending at an angle of 30 degrees. After 6m a smooth boulder marks the beginning of easier hands and knees crawling. The passage has a number of small wet sections before an obvious crawl through a pool (the pool can be bailed and will remain dry for a number of days when there is no rain). The passage then turns left and passes a number of small calcite chambers. Eventually, a 3m climb is encountered (ed. rigged 2011) before a small flat out section.

Just past the flat out crawl an obvious rift in the floor leads to the original 'Bypass' route, which emerges just before the upstream sump. This route is tighter and wetter than the New Bypass route The passage now gets larger and continues to ascent, eventually leading to a large phreatic passage. At this point, and to the left, a large ascending phreatic tube goes via several climbs and a duck (which is frequently sumped), to the Upper Entrance. There are a number of passages here, some unsurveyed. Following the obvious main passage eventually loops back round to connect with the Black Hole. Route finding can be difficult. The way on is over massive potholes in the floor and through a large bedding plane and collapse, until a short climb down marks the start of the Black Hole.

Black Hole to Clapham Junction

The Black Hole is a confusing area of interconnecting passages, many of which lead down to the stream way, all eventually sumping. Navigation is hampered by a black, slippy deposit, which hides all distinguishing marks. However, as a general rule, keep to the left of the passage. An obvious step / climb (marked with a pile of boulders to aid climb) should be reached and following the passage along the left, trending upwards, leads to an obvious orange-tinged 'flow', coming down an ascending passage on the left. Following this passage upwards leads to the obvious junction of Clapham Junction. (ed. 2017 - basic rescue & first aid kit in place).

Left at Clapham Junction, over the pool of water, leads to Outer Mongolia, 10m diameter, slightly downhill passage, splits into a maze of sand and mudchoked side passages and chambers.

Clapham Junction to the Ramp

Clapham Junction is suggested as the best location for a rescue dump in the event of flooding in the main stream way. There are a number of ways on from Clapham Junction. Turning right at Clapham Junction continues to a fork, the passage to the right here opens into a chamber, called Bondi Beach, because of the presence of a huge white sandbank. The chamber slopes steeply down.

Left at the fork gives access to the Roads to Ruin, a clean washed, stream passage with a keyhole cross-section. Sporting traverses and climbs in the vadose canyon open into a phreatic roof tube. On the right a sandy floored chamber provides a way into the Roads to Freedom.

The continuation of the streamway (The Road to Wigan Pier ) leads, via more traverses, to a chamber. At the far end of the chamber a 9m by 3m sump pool (Parting Friends) is perched above a 6m waterfall pitch. Above it was an unclimbed pitch of at least 20m. The main way on from Clapham Junction, is straight on and 100m up a steeply ascending tube. This is The Ramp, which requires a 75m handline (ed. rigged 2016).

About 30m up The Ramp, traverse across slope and follow a steeply ascending branch passage to interesting muddy climbs which resembles much of the Roads to Freedom in general appearance, but choked with calcite after about 50m. At the top of the Ramp, and to the left, a wide tube leads to the beautifully decorated Stalagmite Chamber. Here a 9m rope climb down (ed. rigged pre-2011), leads to the floor of the chamber, following the main way out of the chamber leads a a number of sandy interconnected passages. The main way leads out onto a roof tube above the Road to Certain Death, an obvious stream washed passage. The easiest route through the Road To Certain Death, is to descend as far as possible to the floor of the stream and then traverse up a number of climbs and awkward bends. Eventually, a climb up leads to the bottom of an obvious waterfall (with a small spout at the top). A bolted climb on the right can be rigged to gain access to the Certain Death sump pool at the top of the waterfall.

N.B. Staying high going downstream from the Certain Death waterfall leads to an obvious pitch back to the lower level. This can be rigged, to provide easier access to Certain Death for diving / equipment

A few metres back from the climb down into Stalagmite Chamber is a small crawl on the left. This leads eventually to the well-decorated Bone Passage and the Dragons Lair.

The Ramp to Boulder Hall

The main route from the top of The Ramp is up and to the right, which leads to a sandy passage, and a long hading rift. Awkward crawls can be avoided by ducking down to the right into the Bypass, just before the rift. The Bypass is a series of climbs, in and out of chambers connected by short, wide, sandy crawls. After one of these crawls a wide, steeply ascending tube goes up to the right. This is Orangeade Arcade, which leads over a series of orange mud covered flowstones, ending in a choke. Both the Bypass and the hading rift continue into Boulder Hall.

Boulder Hall to Consort Hall

A peg climb to the right of Boulder Hall leads to approx. 100m of passage and a small chamber. Part way up Boulder Hall a passage / ramp on the right-hand side leads to approx. 300m of interconnected passage and chambers. A small immature stream way is encountered at the end. The end of this passage was dug in 2015 and is approx. 5-10 metres from the surface. Further digging here may reveal a third entrance that would enable teams to bypass the entire entrance series. The entrance would be on the North cliff face of Monte Los Joyos at the end of the Sierra del Corta. From the top left of Boulder Hall, the passage continues until a junction is reached. Down and to the left leads back to the top of the Ramp.

The main way on is a 9m climb (ed. 10m handline - rigged - 2011) followed by a 10m calcite slope (ed. 10m handline - rigged 2011). At the top and to the right the passage soon tightens, but to the left it continues until the 22m pitch is reached. For SRT a 40m rope can be used, following the left hand wall. Backup on an obvious stal boss and follow the calcite slope down to the left and round a column on the edge of the calcite. A hanging rebelay here is followed be another rebelay against the left hand wall, (a long loop attached to the rebelay to aid changeover is recommended) allowing a free hang to the pitch floor.

Down from the bottom of the pitch the phreatic tube continues upwards, Brian Baru's Place, passing several short climbs (ed. all rigged - 2011) until an obvious calcite slope blocks the way. This can be free climbed on the right-hand side. (ed. 12m handline - rigged 2016). The passage continues as before until it appears to end at a second calcite flow. A difficult climb up the flow (ed. rigged - 2011) eventually leads to a small draughting hole (The Howling Hole). An awkward climb leads to a nice section of passage with a small set of pools. The Howling Hole itself no longer howls, but a sizable draft is emitted from a small sump located at the base of the passage, presumably as the water has dropped since the original discovery. The 2011 expedition examined this lead and concluded that only a long term digging project would pass the sump. A small inclined crawl through moonmilk quickly terminates. A climb up smooth calcite deposits for about 8m leads to the base of a small 3m aven. This area of the cave appears to be formed in sandstone and different geological strata. The top of the aven has a small calcite ledge with a low crawl through to another small chamber, full of helictites. The chamber also contains a lot of dead moths and would suggest that the passage is very close to the surface. There is slight draught in the chamber but no obvious way on.

The top ridge of the Sierra del a Corta is approximately 250m vertically above this point. However, the surface on the west side of the Sierra del a Corta is only 150m horizontally, in a straight line.

At the bottom of the climb the main way on is a small hole on the left hand wall, the Hole in the Wall, which leads down to a 5m pitch. From the bottom of the ladder a phreatic tube continues upwards, and eventually drops down and apparently chokes. However, about 10m back from the choke an obvious passage on the left-hand side leads upwards via a climb and veers off to the right, through a number of low crawls and climbs before reaching a low wet crawl (previously the 1m draughting sump)

The low crawl is followed by a series of climbs, all currently handlined (2011) Along and to the right is the 13m Flake Pitch which drops into Flake Pitch chamber. The way on is in the opposite corner of the chamber (not towards the sound of water) and is a climb down into an old, dry, gour pool. (2012 - climb should be approached with caution as slowly degrading)

A steep, very large, partially decayed calcite flow ascends out of Flake Pitch Chamber. 100m of difficult climbing leads to a rift with a small stream, but this becomes too tight to follow. A large rift climbs up, and carries on, past a well decorated chamber on the right-hand side called The Oasis, up a short calcite flow, and over the top of a second, larger flow. On far side of calcite squeezes, just beyond the Oasis a climb of about 50m led to tubes, all of which are choked with calcite.

This leads into a large boulder filled chamber, which is followed down into a rift, and eventually to a 12m pitch into Consort Hall.

In the rift 20m before the 12m pitch down to Consort Hall is reached is the start of the I Love Horses ramp. This begins as a climb out of the rift for 10m before the ascending passageway can be seen. 60m of rope is rigged on stal naturals and secured at the top of a slippy calcite ramp with a natural and bolt. An obvious continuation is followed up a short calcite climb, best taken on the left. This needs 8m hand line which can be rigged from a stal. Beyond the climb, the passage opens out into a 4x20m chamber with impressive formations. At the far end another ramp leads up to a calcite choke. This can be passed by a very tight squeeze Morning Sickness on the right. Beyond the squeeze is a further 11m ramp. No way on at top.

Opposite the pitch into camp a 20m climb up the ramp leads to 30m of large muddy phreatic passage. Ends in a 'mud sump'. There is no draft in the area.

Consort Hall to Hall of the Green Domino

At the opposite end of the Consort Hall chamber a sandy crawl leads into a large phreatic tube which continues past an intrusive stream, through some impressive sections of passage, The Ripper and then Big Country, to the bottom of the steep rift climb of Son of Ramp, which requires a 40m handline (ed. - rigged 2011). The top of this ramp is a steep calcite slope which requires care.

The rift continues on over several calcite slopes, to the bottom of a 13m calcite flow, which can be free climbed 10m back into the rift. (ed. - rigged 2011). At the top a large phreatic tube continues down to an obvious junction. Down eventually becomes too tight, but up continues through very old phreatic passage until it suddenly becomes much smaller. The smaller way on down, leads through tight rifts to a 17m pitch into a chamber with no way out. However, where the passage becomes smaller, a climb up on the left (ed. - rigged 2011) leads to the bottom of a phreatic shaft, which required pegging. This requires a 15m rope (ed. - rigged 2016). At the top of this climb is a large chamber, the obvious way on being a 30m broken pitch, The Big Rift. Descend the 30m pitch followed closely by a 7m pitch. A further 8m pitch should not be descended and the route is along a traverse on the right-hand side (ed. rigged 2011). A few steps beyond the traverse the rift opens out into the boulder floored chamber called the Hall of the Green Domino.

Dan's Big Room.

A hole in the top of the calcite flow, at the head of the Big Rift pitch, leads down over boulders to a 6m pitch. A large phreatic passage now continues up. Some fine tree formations are reached, and just past these a climb up to the left leads to Dan's Big Room. Straight on is a large, boulder filled chamber, to the top and left of which are several areas of fine formations. Carrying on further the passage eventually chokes with sand, but 12m into the roof another large ascending passage can be reached by a difficult over-hanging peg climb. A maze of unexplored passages continues above.

Pitches leading to the Bloody Lake.

Following the phreatic route out of Dan's Big Room leads eventually to the choked Terminal Chamber. Below the climb up to the collapse area is a vertical slot which, though fairly constricted for the first 30m opens out and after about 100m reaches the Bloody Lake. This shaft is also entered by the 'Windy Spruce' passage which leads off the Grand Circle on the Bloody Lake side to Scrambled Egg Chamber

The Bowling Alley.

Following the phreatic passage out of Dan's Big Room brings you, after 20m, to a passage leading off to the right. Easy passage leads to a climb on treacherous calcite, and then a 10m bolt climb gives access to Pork Scratching Rift (17m high, 0.5m wide). From a small chamber the passage continues through a low arch into a chamber 30m by 30m, Glove Chamber. A 5m slope descends to a 13m pitch into the Terminal Chamber.

Hall of the Green Domino, Bloody Lake, Colins Climax and the Grand Circle.

From the Hall of the Green Domino the route along the right-hand wall leads to a 11m pitch (ed. - rigged 2011), from the base of which there are two main ways leading off left to the Grand Circle route and right to the Bloody Lake. From the Bloody Lake an 8m pitch up (ed. rigged pre-2011) enters a window in a large calcite flow immediately followed by a 9m pitch down (ed. - rigged 2012) into a phreatic tube. Easy going, walking up and down in the passage, passes the 9m Rendezvous Pitch on the right hand side (ed. - re-rigged 2012) before eventually ending at Colin's Climax, the main stream way.

Going up at Rendezvous Pitch is the easy, tackle light option to get to the main upstream sump. At the top follow the main passage over boulders, turning left at some popcorn like formations before joining up with the boulder slope (found at foot of 30m pitch) that heads down to the sump. Turning left from the bottom of the 11m pitch, into the Grand Circle, proceed along dry boulder strewn passage with maze like proportions to a 22m pitch. The pitch is constricted at the top but later opens out into a large chamber. Large passages extend both right and left from the bottom of the pitch. The left-hand passage soon develops into awkward walking passage, stumbling over boulders, climbing calcite flows and traversing holes that eventually drop into the stream way below. This passage, which appears to be a high level route in the roof of a stream way canyon, ends at an 11m pitch which drops down to a point where it is possible to traverse along the rift wall and step down to the stream way. A few metres below the 11m pitch a small passage enters from the right and following this for about five minutes leads into a phreatic tube going towards Colin's Climax.

Returning to the Hall of the Green Domino, a climb down, on the right, between boulders before the 11m pitch leads to a chamber. A two metre climb up the far side has many small tubes heading away from it, most of which interconnect at various stages. At the northern end of the maze a rift opens into a chamber, the start of the Grand Circle. Although a possible free climb to the floor of this chamber is possible, a ladder certainly helps. A large phreatic tube at the far end of the chamber rapidly turns into a flat out crawl, opening out into a pleasant trading phreatic passage. Traversing around pools and stooping below formations eventually ends at a 12m pitch immediately followed by a 30m pitch. Descending down to the bottom of the boulder slope, at the base of the pitch, the stream way is found to the right is the Main Upstream Sump pool whilst to the left the water cascades down in a high rift. The opposite direction at the bottom of the 30m pitch continues along a small rift, eventually emerging at the 9m Rendezvous Pitch, which lands in the sandy passage just prior to Colin's Climax. This point can also be reached by a climb above the 30m pitch which leads into a passage, also emerging at the head of the Rendezvous pitch.

The '150' Series the Booming Catacombs

Climb up from the foot of the ladder that descends to the Bloody Lake from the Hall of the Green Domino into the maze. The marked route leads to a 22m pitch into a chamber. The right hand exit leads into a heavily calcited rift, followed by a 5m climb into a perched pool and then a 30m descending pitch (the so-called 150' Pitch). Two ways lead off. To the right by means of a slot and three pitches (10m, 10m and 8m) a small streamway is reached, which sumps in both directions. To the left from the foot of the 30m pitch you descend into a sandy chamber with a small stream sinking in the floor. A rift leads to a large cavern, also sandy with large rock pillars. There are several exits. On the left, a large rift can be followed for some distance but closes down. Following the wall clockwise several passages lead to oxbows or choke. At the far end of the chamber, a 17m pitch descends to the Booming Catacombs (this pitch can be by-passed by a crawl to the left of the pitch) which comprises a mud caked phreatic passage, deep with static pools. After about 150m this leads to a vertical shaft, completely flooded after 13m.

Passages off the Grand Circle.

A hole in the floor of Scrambled Egg Chamber can be descended for about 27m and reaches part of the maze from which another 30m descent leads to the start of the '150' series. Continuing anti-clockwise around the Grand Circle, on the left, immediately before Aven Y-Y, a large passage (8m wide and 2m high) climbs steeply out of flowstone passage but decreases in size and finally drops into the Circle again at Aven X-X.

Colin's Climax to Main Stream way passage.
From Colin's Climax about 100m of swimming and traversing leads to an upstream sump. The Main Upstream sump has been dived for approx. 300m in a large passage to a depth of -45m, still continuing. Downstream can be followed for 300m in superb style to a magnificent chamber and another sump.

Road to Certain Death

The Road to Certain Death sump was dived to a depth of -64m at 210 m from base, at which point an ascending shaft was encountered but could not be followed for decompression restrictions. (ed. 2012 this may not be correct? Passed by GN, no ascending shaft and continuing at depth?)

Road to Wigan Pier, Road to Mandalay and Parting Friends

The Road to Wigan Pier sump has been dived, at a depth of -17m, and continues for 180m before rising into more stream way. 300m of passage, The Road to Mandalay, leads to a 4m waterfall and at the top a small section of stream way leads to another sump (Parting Friends). A tight grovely bypass to the Wigan Pier sump is possible The Parting Friends sump was passed in 1999, it is an 8m long sump to a largish chamber. A second sump here was dived for 150 - 200m at 10 - 20m depth and continues in open passage The water from Cueva del Marniosa was assumed to reappear in this Western section of Nacimiento. (ed. 2017: Sump 2 in the Marniosa - "1986 Extensions" is approx. 500m horizontally and 50-100m vertically from Agua, halfway between Parting Friends and the Far Upstream Sump, and as of 2017, appears not to be draining in this direction)

Teeth of Satan, Twilight Zone and Death Race 2000

In the Hall of the Green Domino follow the left hand wall until above the Bloody Lake, on the left hand side is an obvious steep climb, covered in popcorn like formations. This is the Beast's Ramp (ed. rigged pre-2011) and leads to the Teeth of Satan climbs.

Ascending the ramp, via a lot of glutinous mud, quickly leads to Satan's Ramp. More steep ramps lead to an obvious Wet Aven coming in on the left.

The Wet Aven

A small stream enters via the aven and an obvious ledge can be seen approximately 27m up the aven. The aven continues, past the ledge, to 40m high. At this point the aven becomes more rift like and can be free climbed with good naturals. A short up pitch leads to a cross rift, the right hand passage closing down quickly, but the other way breaks out into another rift (3x x 5m) and a 10m aven. The top of this aven then leads to two more small 'up' pitches, with the final section reaching a constriction at the top The ongoing lead requires some digging / capping of a small amount of calcite and is fairly wet as a small stream enters at this point. A draught and small stream enters through the constriction and it would appear to be a chamber (with a good echo) and another aven above, approx. 10m high. water. The aven and subsequent pots total over 60m in height and the avens are currently rigged all the way to beneath the final constriction
Continuing past the Wet Aven, a climb up here soon leads to the actual Teeth of Satan, an obvious junction with some fang like formations.

Left here leads to an ascending, well decorated passage. A few calcite climbs must be negotiated before the passage slowly narrows. A duck under the right hand wall leads to a 4m climb up to a window looking into a wet aven. The top of the aven narrows and down heads back under the known passage.

Satan's Chode(a.k.a. The Twilight Zone)

From the Teeth of Satan, a 4m climb on the right-hand side gains a gently ascending ramp on well sculpted rock. Following this leads to an ascending rope series (ed. re-rigged from naturals in 2018), culminating in a large phreatic passage trending away from the Teeth of Satan. This passage can be followed for some 70m to well decorated chamber containing a climb up and a pitch down. The climb leads to a further 60m of extraordinary formations, ending in a mud choke. The pitch down (~10m) remains unexplored, however, it is likely to have been explored in the 80's as some solitary footprints were spotted.

Access to the upper series now requires a steep (but safe) climb out of Satan's Chode, this is the first rift on the right-hand side after the pitch head. This climb is ~15m and steep and ends in a rift. Straight on leads towards the original access point to this area, a steeply ascending calcite ramp (now de-rigged). There is also a short 3-4m climb near the ramp which has not been passed. Although assumed to be an alcove, a draught was detectable here during the original exploration (2014). Back at the top of the climb, the passage turns right to a series of narrow rifts on 3 levels containing some unique formations. In this rift are several unexplored downward leads, these are all narrow and take a slight draft. It is assumed these connect with the main trunk passage below, Satan's Chode. There is a small amount of air movement throughout the upper series.

Death Race 2000

Continuing under and straight on at the Teeth of Satan a further steep ramp, Hellsmouth, continues up, via more ramps, until an obvious horizontal section of passage is encountered. Following the rift (and an obvious draught) leads through a number of chambers. An obvious sharp left turn marks the P Chamber area. There are a number of side passages here with leads (see survey). 15m before P Chamber, just after an obvious sharp right-hand bend when coming in to the cave, is a small aven. This begins as a small climb on delicate popcorn calcite to a ledge. A tight rift leads to an exposed climb in the main rift to a calcite flow ramp. This is ongoing but very tight. The rift continues east for 8m and is ongoing and offers more potential for progress.

The Silky Carpet (above the Death Race Rift)

Starting from the well decorated chamber above the Be More Arwel Aven there is a steep calcite climb in the back corner and an ascending ramp trending back over the main Death Race rift. The calcite climb chokes out after 10-15m however, the ascending ramp leads to 100m of breakdown passage, The Silky Carpet. At the top of the ramp is a large square chamber with two ways on. Left leads directly to an undescended 8-12m pitch back into the main passage. However, the pitch is broken at -5m where approx. 20-30m of continuation passage can be seen to head towards a rock arch (estimate 2-3m high). It was not possible to see beyond the arch and it is entirely feasible the passage continues. This presents an interesting lead as it trends away from the main rift. None of this section was explored. A strong draught was felt down the right-hand passage of the square chamber. This was followed for approx. ~100m via a series of short calcite climbs to eventually reach an eyehole back into the main Death Race Rift. Three climbs were noticed and two were attempted, but these quickly choked out in calcite. The last climb was quite steep and headed directly towards a large area of stal, so further progress is unlikely. The large square chamber of the Silky Carpet can be obtained via a short pitch series, beginning at the base of the Be More Arwel aven.

Following the main passage a few more climbs are navigated before reaching a traverse (ed. rigged) and a pitch down. A further pitch down and then up (ed. rigged) leads to the large Death Race 2000 chamber. Here 2 avens enter over the deepest part. The chamber itself is filled with huge boulders and over 150m of rope is required to reach the bottom of the chamber, approx. 70m below the entry point into the chamber. At the bottom of the chamber, a small immature stream way, the Pitch Series, has been pushed for approx.. 700m and -175m depth. At the bottom a 20m pitch leads to a low wet crawl, alternatively a pendulum across to an obvious eye hole provides an easy route (30m rope) to the other side of the wet crawl. A further 2m climb leads to a pitch / ramp of 20m following the stream. Another 5m pitch lands in a high rift that continues for approx. 30m in a northerly direction, traversing across a deep pool of water to a window and 5m pitch into the sump chamber (Pena Colada Sump). The sump chamber is 35m long by 5m wide by 25m high. The sump itself was not entered and there is no obvious flow of water which suggests it may be a deep phreatic trunk route with water moving slowly, at great depth, past an 'airbell aven' There is also a potential dry lead over the top of the sump that has not been explored. The level of the sump is consistent with the level at the main upstream sump near Colin's Climax.

The Bastard’s Ramp

Following the rift leading out form the Pina Colada sump there are two short flowstone ramps, each rigged as a straight drop with a single bolt (both requiring a decent back up). A final short climb, best tackled on the left, leads to Here's What You Could Have Won (HWYCHW), a spectacular large passage with a mud floor.

Turning left at the top of the ramps leads through some muddy slopes to a closing down of the passage, where there are two holes in the floor. Being directly above the Pina Colada sump, it is presumed the furthermost one will lead back down to the far side of the sump - an interesting lead as this is not easy to view from the rope traverse around the sump. The nearer hole in the floor is likely to also link with the sump pool, probably via a more convoluted route. Neither of these holes exhibits a draft.

Turning right at the top of the ramps brings you to an impressive flowstone pitch of 40m. This can be climbed by a rope on the wall opposite the entrance to the passage, follow the rock ledge and then a longer 25m rope takes you up the main pitch in a single drop. Here, a suicidal descending traverse has been rigged to a column - the jury is out as to whether this is worse on the return journey.

Once you have stopped swearing at the rigging, a further rope can be followed up to a y-hang in calcite. Two ropes lead out from this point, the more obvious way continues up the flowstone, to a final 4m pitch, the passage continues for a short distance and further climb to end in a well decorated calcite choke.

Back at the y-hang, straight up leads to a tri-hang in shattered rock and a short section of level passage. The rock here is of similar structure to the stream passages underneath Death Race, although fortunately much larger, it doesn't inspire confidence. There are a few alcoves, all close quite quickly.

The most obvious climb looks a bit dubious this far into the cave, however ducking underneath reveals a chimney alternative, squirming up here leads to a reasonably sized ascending phreatic tube, in slightly more reliable rock. A second 2m climb leads to more of the same. Being of phreatic nature, the rock is honeycombed with many possible ways on, most small and leading back to the same passage.

The original exploration remained in the obvious passage and ended with three possible ways on. A short down climb into more horizontal passage and a steepening of the ramp where there appears to be a roof and possible horizontal passage beyond. This is estimated at 5m and will likely prove simple to pass as a mixed aid/free climb, but a rope would probably be wanted for descent. The passage also continues, now at a considerably steeper angle. This section has not been surveyed.

Around Death Race 2000

An Evening Stroll is accessed direct from the Death Race 2000 chamber (station 1201) and is a series of climbs (C4, C5, C3) that overlook the main chamber. The passage extends for 66m, reaching a height of +406m above the main entrance. The top of the passage is choked with stal but lies only 5m directly below the main passage in Die Hard. There is a small lead heading down near the start of the passage.

One aven in Death Race 2000 has been climbed approx. 60m off to a small chamber. A climb (starting station 2203), called Dirty Pretty Liars, leads to another 70m of passage with a further height gain of 50m. This highest point is +486m above the cave entrance. There were no further leads at this point. Additionally, another lead in the same area was followed down 10m to a small sump.

Directly behind the Death Race 2000 camp, in the vicinity of An Evening Stroll is a descending rift, Joes Crack. The entrance to the rift is just beyond the camp in the wall, stoop under a boulder leads to a narrowing passage that quickly becomes a tight rift which narrows downwards. Part way along the rift widens slightly and a pitch can be descended for 8m to the floor of the rift.

The pitch starts off incredibly tight, but widens towards the bottom. At the bottom of the pitch the floor of the rift dips downward in a direction beneath the tight traverse above. The upslope quickly ends, but down slope can be followed for a short distance. Here the passage is approximately two metres wide, narrowing upwards, and the walls are covered in brittle calcite.

Turning right at the brittle calcite leads to a pitch series, currently rigged (2018) with a single 50m rope from here to the end of the extension. The rope ends in a loose boulder choke (caution) and a way on down through the boulders follows a small stream before quickly ending. Heading forward it is possible to pass through a narrow slot into a sizeable chamber. This chamber contains a dry aven and an inlet passage, neither of which have been explored. The inlet passage does not appear too steep, is quite sizeable and could provide some entertaining upwards exploration without too much effort. The dry aven will need climbing gear.

An interesting part of the cave, and another inlet that could be followed with interest. It is likely to be upstream of the water that appears at the base of the Death Race water pitches, before reaching the Pina Colada streamway.

Die Hard

From station 2208 in the Death Race 2000 Aven Series a passage descends down a 8m pitch, followed by a ramp of 10m, and another 6m pitch before a final 10m ramp leads to a bold traverse of 30m around the Death Race 2000 chamber. At the far side of the traverse an ascending ramp of 10m in an impressive sized passage leads to a further 5m pitch. A large passage continues for 40m, passing under 3 unclimbed avens, before narrowing, where the main draft is encountered. The passage widens once more into a large chamber, with 2 more unclimbed avens. The passage narrows again and swings south for another 50m before climbs of 5m and 3m enters a large rift / chamber with 3 unclimbed avens. Just beyond the Death Race 2000 traverse, heading into the Die Hard passage a squeeze on the right can be passed to the base of a rift, with numerous calcite mushroom formations. The rift, I'm Not Into Yoga, can be climbed to a height of over 60m to a tight continuation (with no draught). A ledge approx. 18m up the rift, leads to two side passages. One closing down almost immediately and the other leading back down to the Die Hard passage, re-joining approx. 20m further along from the start of I'm Not Into Yoga. Approx. 25m after the Death Race 2000 traverse, heading along the Die Hard passage is a small climb on the left. This is an easy climb to Sand or Smeg chamber, a large, but short passage consisting of a collapse at both ends. A bit further beyond the start of Sand or Smeg Chamber, within the obvious Die Hard meanders it may be possible to push a short climb into a rift above the meander, however, this probably connects to the Dinosaur Aven further along, but was not attempted.

Better than Digging

By the left wall of the Die Hard passage, opposite the final bolt of the Die Hard traverse, is a smooth calcite lump. Behind this, is the Better than Digging aven. Initially this is climbed in a rifty chimney for 12m to reach a small ledge and a window back into the main passage. Above here, the aven opens out slightly. Climbing up to the left and up the centre, on loose mud and calcite, it is possible to get most of the way up the aven, however no obvious way on can be seen, and no draught is present.

M6 Toll Bypass Jurassic Highway

From station 2208 in the Death Race 2000 Aven Series a passage descends down an 8m pitch, followed by a calcite ramp of 10m, and another 6m pitch before a final 10m steep ramp leads to a bold traverse of 30m around the Death Race 2000 chamber. The M6 Toll Bypass begins at the start of the 30m Die Hard traverse. The pitches are left rigged above so that station 2208 (the high point of the Death Race Avens) can still be reached. However, the original access route from Death Race has been fully derigged, and thus the passage above and beyond (Dirty Pretty Liar) can now only be reached by the M6 Toll Bypass. The M6 Toll Bypass begins from the start of the original aid climb, the far side of the Death Race chamber from camp, and up a short leftward traversing scramble. The M6 Toll Bypass traverses out left on mud, and ascends a short pitch to a rebelay. At this point a step down and out onto the left wall reaches a ~20m pitch on steep calcite with a rebelay. A short traverse at the top of the pitch gains the Die-Hard traverse (ropes from previous access route are left in situ). Jurassic World In the final rift / chamber of Die Hard a short muddy ascending traverse for ~8m leads to base of a large aven (20m+) in the rift. A window 5m higher, beyond the aven, is unexplored but the way on is down a small opening at the base of the aven accessed via single bolt rebelay landing on a small false floor. A short 4m climb is followed by a stoop into a 2nd larger aven (The Dinosaur Aven ~30m+) with an active inlet and a 'lake' floor. The unexplored window in the previous rift chamber probably links into this aven. The first part of Dinosaur aven is 20m high, a further 10m rift in the aven leads to an obvious window that overlooks Jurassic World, 20m below. The main aven continues for another 30m with a number of ledges. At the top of this section the passage starts to narrow to a small crack. This has been widened and leads to a tight meander for approx. 10m to a constriction. The aven is currently still rigged, with a double bolted re-belay positioned in a useful place for traversing back into the main aven, which is still on-going and dry. Crossing the pool an 8m climb up (hand line) is reached. The top of this climb enters a large passage Jurassic World, similar in characteristics of the passage approaching the Death Race 2000 chamber. Trending upwards two muddy calcite/moon milk ramps are rigged as pitches, followed by a climb up towards a well decorated chamber. A stal boss is passed on the right into a small well decorated rift. A hand line climb up a stal at the far side is followed immediately by a climb down back into the main passage. A steep calcite ramp can be bypassed by an obscure tube at the base. A further 50m of passage is followed under 4 unclimbed avens / inlets. The passage leads to a small sandy area and a hole (opened 2021) leading to Barney & Friends.

Jurassic World – Barney and Friends

Jurassic World ends where the mud rises to the ceiling. On the back wall (left side) an enlarged 3m crawl steps down and then squeezes steeply upwards one body length to emerge into larger passage. Passing a blind alcove on the left, a short climb up leads to a short narrow rift to crawl across and an awkward climb back down over delicate rock, back into easy going mud floored passage.

A flowstone constriction leads to a continuation of the passage, split by a large flowstone formation. The passage on the left ascends 2 short climbs and ends with a blind pitch back down to floor level. Right leads to a further large passage and after climbing up and back down a rock bridge Barney the Stalagmite is encountered (Barney is very purple).

A short climb beyond Barney leads to gently ascending passage and a further large flowstone formation. (Below this a 10m blind hole in the floor, the hole can be stepped over to then free climb the large flowstone). Climbing the right of the flowstone leads to an awkward step (traverse line required) before flattening out at large gour pools.

At this point the passage splits again. Some intricate crystal gour pools head left and up toward an obvious passage. To preserve the formations, please do not enter this as it has been accessed from above and shown to close and join back with the right hand route.

Around to the right a 7m pitch is rigged as a single drop from a large natural. Left at the top leads to the top of the gour pool passage. Straight ahead an ascending passage narrows with flowstone walls. Soon a further up pitch is reached, split by a rebelay to the final calcite choke - Leo's Blowing Crack.

Leo's Blowing Crack is a calcite choke, with a 1/2 body sized hole, through which a strong draft emerges. Capping of the corner entering the space will give more space to work.

Pterodactyl Crumble

Toward the end of Jurassic World several high-level leads and avens are found. The first one attempted in 2017 was climbed to Pterodactyl Crumble. It is accessed via some acrobatic moves directly above the small "rat" hole climb in Jurassic World. Pterodactyl Crumble consists of a series of low sandy chambers ~12m above floor level. The first of these chambers is littered with bat skeletons. Although initially exciting, the obvious way on soon loops round and back into the main passage as an oxbow. Part way along this oxbow a low crawl trending away from Jurassic World. After 10m this breaks into a larger boulder chamber trending downhill. The final 15m can be rigged as a pitch to a 'mud sump', however there is no draft and no way on. Part way along the left-hand side a narrow tube leads to a flat-out crawl of 5m to a mud sump. The entire series was de-rigged. Any attempt to re-gain should be approached with caution as the rock is very brittle.

Terror Firma

Around 20m before the end of Jurassic World and the sandy dig, is an inlet aven, Terror Firma, where an obvious 6m deep choked pot has formed from the water entering via the aven. The aven is gained from a bridge between the pot and a muddy slope down. A swing out under the dripping inlet leads to a dry 15m pitch up to the water inlet. Beyond this the main aven continues, ending at a roof after 10m The water inlet is entered via a slot (3m wide, 2m high) and is then followed ascending at a 60-degree angle. The muddy slot is traversed for 10m before it opens out and continues. At this point the aven splits. To the right is a dry old brittle breakdown passage which has been climbed on brittle rock for approx. 12m to a calcite ledge. The aven then closes up to an impassable slot with no apparent way on beyond (a rock in the tight area could be capped in order to take a closer look to see if the passage continues as a tight way on around a corner due to the lack of draught, it is unlikely that this way continues.) This aven has been derigged back to the ledge at the exit of the muddy slot. From the ledge beyond the muddy slot, the wet muddy way continues up, Actual Terror. The passage is easily free climbable for 3m and a way on through a window following the water continues to another ledge. An awkward exposed step (rope and long legs recommended) enters the ledge, and continues with an awkward climb, this ends after 10m with the water entering through a narrow impassable crack. A rope is required for ascent/descent. There is little prospect remaining in the avens of this region.

Terror Firma / Actual Terror marks the current highest point in Nacimiento at +535 above the entrance.


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Colectivo espeleol'gico que agrupa, al menos, a miembros de los grupos franceses G. S. Romans, G. S. Valentinois y S. C. Vercors.
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Crossing the entrance pool Entrance to Nacimento The Dragons Lair Cueva del Nacimiento (Plan)