Tresviso Caves Project

Tresviso Caves Project Gazetter

2.6: Sara

(Sistema Sara, Sistema de la Mina Sara, AN-9, Sima Sara, Cueva Sera)

Area:Vegas de Andara
East, North:361437, 4785242 (nearby)
Coordinate Quality:GPS
Long, Lat:-4.7057123782387, 43.2072194992 (map)
Elevation (m):1820
Length (m):4000
Depth (m):-644
System:Sistema Sara
Active Lead:
Survey Available:


The entrance is on the west side of an extensively mined valley basin, situated between the peaks of Samelar, San Carlos and Mancondiu.

Starting at Caseton de Andara (The White House), take the obvious zig-zag tracks that head up the spoil heaps directly behind the refugio. An obvious junction is rached (marked with an enclosed red tinted pool), to the right leads to Pozo de Andara (the Lake Depression) but left heads toward an obvious col to the South of Mancondiu.

This is the quickest way to Vegas de Andara (the Sara Depression) and an obvious track can be followed all the way into the depression. Sara is the obvious largest spoil heap to the west of the depression.

The T78 entrance is located above the main Sara entrance. Follow the obvious miner’s track on the before entering the Sara spoil heaps and follow it to the top of the ridge. T78 is the final entrance at the top.


The partially collapsed entrance is directly above a large spoil heap. A very strong draught emanates from the entrance. The entrance is in a dangerous state of collapse. Entrance via T78 is advisable. Entrance


Note: The Sara system consists of many mine passages and entrances. The natural system is divided into two main sections. Sara I is a shallow cave into which Sara IV connects. Sara II is the name given from the Heinous Shaft, to the the main stream cave, to the original sump and the Rio Mancondiu series. Sara III connects into the main system higher up the Heinous Shaft, and is best accessed from the T78 entrance. The depth, from the T78 entrance to the furthest point in the Terminal Sump is -644m

From the main SARA entrance, a crawl in through collapsed boulders leads to walking size mine passage. Follow the passage for 100m until a junction is reached. Left leads to Sara II, right leads to Sara I and Sara III.

Sara I

The right-hand route continues as mine passage passing thought and above numerous mine workings. A turn on the right leads to Sara III. The first pitch is 16m to a canyon passage. Upwards soon chokes but downwards a descending passage leads to a 4m and 14m pitch in an impressive shaft.

A small climb up at the foot of the P14 leads to the Reseau Perspehone series. This is approx. 40m long with a number of unexplored avens and a rift type meander at the end

A large phreatic tube continues steeply downwards to a 3m pitch and 50m of sporting climbs. After passing a small boulder chamber and down a 30-degree ramp, the final pitch of 30m is reached. Below a small silted tube soon sumps.

Sara IV

Shortly before Sara I take the left hand turn into mined passage. The passage forks and taking the left-hand route reaches a shaft in the right hand wall. A P12 past obstacles reaches a wooden platform, above a flooded shaft. Across the planks, through a passage on the left reaches a high rift. Past another flooded passage on the right, reaches an impressive passage full of stemples. Passage descends to small hole and climb down into tight rift to enter above the P4 (second pitch) in Sara I

Sara III

The right-hand passage leads to a further junction, left leading up towards T82 Karen and numerous surface entrances (T79, T80, T81 T84 and T92). Right leads to a 3m climb up and further mine passage, passing a flooded shaft on the left and after another 10m a climb up at the end. A crawl under a large boulder leads to the tight take-off the first pitch down the Heinous Shaft (Pozo de los Culebrones) (with pitches of P34, P70 and P125) landing on the same boulder pile at the bottom of the shaft. This route is not as wet!

Sara II

Back at the main junction from the entrance, the left turn leads to a scramble over mine debris to the first pitch in Sara (Sara II) The bottom of this a 6m drop lands on a sloping boulder floor and the way on is via a 2m climb and a crawl. Branching to the left the second pitch of 7m is reached. From the bottom of this, a slope of mine rubble leads to the next pitch of 12m, narrow at the top, but opening out straight away. This lands part way up a narrow rift, which soon becomes low as well as tight. It joins another inlet passage at a difficult 2m climb. A short traverse leads to the head of the 180m Heinous Shaft. This can be descended with rebelays at 28m, 32m, 35m and 88m.

The final 88m pitch lands on a sloping, boulder floor. In the top most corner of the boulder choke a ladder climb down a loose boulder tube leads to a free hanging 52m pitch in an impressive rift.

The pitch lands on a large boulder floor. The route on is up the boulder slope and then down to the right. After a short distance the streamway is re-joined just before the next pitch of 12m, which is wet at the bottom. The water soon sinks into boulders and the way on is up to the right. At the top of a muddy boulder slope is an awkward 2m climb down to the head of a 24m drop. Free hanging all the way the pitch lands on a large boulder ledge. Climbing down to the chamber floor the streamway is reached.

A climb of 10m from here leads to Rio Mancondiu extensions.

The way on soon becomes low and a crawl for 10m leads to a 2m climb down into a large pool. The way on is to traverse at various levels until an 8m pitch is reached. This lands in a pool in a moderately sized chamber, historically the site of underground camps. An unclimbed aven enters above this chamber.

Continuing on from the chamber soon leads to more traversing and climbs until, after 50m, the passage widens and a short duck is reached. From the other side of the duck a series of short cascades and climbs lead to a muddy ledge which must be traversed to reach the head of the next pitch which is 10m long. This lands in large, water washed passage and the way on is down a series of sporting pitches the lengths of which are 5m, 10m, 6m, 16m, 5m, 14m and 12m, the last of which is particularly wet due to inlets entering from high in the roof. A climb, followed by a short walk and traverse leads to the head of an impressive 43m pitch which again is wet at the bottom.

From the 6m pitch a route over the top can bypass the next 3 pitches to a 27m pitch at the head of the 14m pitch. The route can be followed further, at high level, under an unclimbed inlet to a P10 and P46, dropping in just after the P43. There are further climbs in this high level that have not been attempted.

Pitches of 9m and 8m follow immediately. From the bottom of the next 8m pitch the dry oxbow route is taken to the head of a dry 7m pitch.

A climb up boulders here leads to an unclimbed aven (probably part of higher level above the P43) and a passage looking down over the main route.

After only 10m the next drop of 23m is reached. This lands amongst spray and boulders in a large chamber.

The way on is opposite the last pitch, along a narrow rift passage. The floor soon drops away and a traverse for 10m leads to the head of the next pitch of 24m. The pitch lands under the full force of the water on a small ledge. Pitches of 11m, 9m and 4m follow rapidly.

At this point the cave takes a more horizontal line in impressive sporting meanders. After about 80m a small chamber is reached. The way on is up and over a large boulder. At this point the passage narrows and the way on involves a series of traverses, climbs and tight squeezes. Not far after the last climb of 5m the passage once again opens out into generous proportions.

Several inlets enter the cave at this point contributing significantly to the size of the streamway. Continuing on at stream level soon leads to the last pitch of 9m. This lands in a spacious, mud floored chamber.

A ramp / climb of 10m leads to pitches of 18m, 6m and 6m dropping back into the rift main passage below.

Walking to the far end of the chamber the streamway enters a huge rift passage, The Sara Depression. After a short distance the passage is blocked by large fallen boulders. The easiest way on is along a low wet crawl to the left of the passage, after 30m the crawl re-joins the main passage. Only 10m on from this the Sara terminal sump is reached (at -591m)

A climb up leads to a 10m pitch that drops back to the sump.

The Terminal Sump was dived in 2022 and currently extends for 34m, reaching a depth of -12m. The sump is low, silty and has almost zero visibility.

Rio Mancondiu. Starting as a narrow rift it climbs up for approximately 30m before continuing down as a narrow rift. The extension is interesting as although it collects many inlets and has many fossil passages leading off, it never acts as a main drain as the waters quickly exit through the floor. The extension ends in a sump. This appears to be 20m directly above the Sara 2 sump. There may be a bypass but this may just drop into Sara 2

A 10m climb up leads to a narrow rift, a 4m ramp and then a 3m ramp to a meander, Wilfrieds Tunneltje, which is 250m of awkward passage, eventually reaching a sandy crawl and a large cold draft. A tight squeeze leads down to a P41 called Frank's Fantasie. The pitch is exceedingly muddy and slippery and leads to a P5.

A 230m long nasty rift (Dre's Miserie) follows, that gets progressively worse and generally should be followed at its highest point. Anna's Pot, a P10, follows leading to a lot of crawling passage to a P22 and a P7. The P7 is very wet and followed by a split P17(?) pitch, to a chamber (1987 camp site, approx. 4 hours from entrance once rigged).

A P18 and a muddy P12 follow (Koen's Kot) to a muddy rift and crawl to a P6 (Jan's Jolijt). A 20m meander leads to big and wet P40 (Wim's Waterval). A nasty, wet and cold rift continues for 20m to a junction.

Left at the junction leads up for 100m, via easy walking passage, to a small quiet chamber (Bieke's Zaal). An unclimbed c4 may lead to a continuation of the passage. Good place for a camp but no water

Right at the junction leads to another meander and a P15 to a large platform (Patrick's Paniek). 30m of meander arrives at the next pitch, a P5, to 200m of meander, a 3m ramp and another P5. A lot of the passage is narrow and unstable.

At the end of the rift is a small chamber, and then another meander to a P41. A continuation of the meander may be seen on the far side of the pitch head.

The P41 lands in a circular sump pool, with no apparent way on at -571m depth.

Note: The survey of sara suggests that the Rio Mancondiu sump is 20m directly above the main Sara sump! Following discussion with the original explorers, due to difficulties with surveying equipment, corrections to heights etc. it is thought that these sumps are most likely to be the same sump. The final P41 possibly being direct into the sump pool, just beyond the main Sara Depression sump pool.


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Tresviso Caves Project (2022)


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