Updated 25th May, 16th, 24th October 2011; 7th January 2018; 21st May 2023

Pulley and slings were required to remove tyres out of this hole. A hole through the tyres near the track gave 10m of passage. At the opposite side a dig down the slope came to a tight section. This was passed to a 10m pitch to a chamber with bags of dead cows , tyres and bones. There are three downward ways off. One goes to a drop whch takes 4 - 5 seconds for rocks to hit the bottom.
However, a bolt was found at the top of the 35m pitch and further exploration has been suspended pending a serarch for more information re previous exploration. There is a lot of loose material on the pitches.

Further explorations occurred over Easter 2011 and the following description was written after these trips.

   El Suto is situated 200 m along the right track and into a small copse immediately in the field on the left. It appears to have been partly explored earlier judging by the evidence of spits in some places. The rock is loose and friable in many places. Nearly all the development of the hole consists of shafts elongated along 261° magnetic.
   The main entrance (now with tyres strewn around) is a covered 1m by 2m slit in wet earth with a solid back wall into which two spits for a Y-hang have been placed about 1.5m down for a rope length of 15m. A second entrance emerges from inside tyres in an adjacent hole and joins the shaft a couple of metres below the Y-hang. It is advantageous to hang a 12m ladder from the base of trees to reach a muddy three-ways chamber strewn with tyres, bones and other rubbish. In most weathers a dribble of water falls from under a sandstone shelf 3m down from the entrance to sink in the first chamber.
  Under a shelf in the chamber to the left a 2m slanting climb down leads to a 4m scramble to a point where the passage is too tight. It leads to shafts seen below, judging by voice connection.
    Ahead, along the 250° magnetic bearing is 1m wide passage that leads after 12m to the head of a pitch. There is an old spit low in the right wall. The rope from the right wall Y-hang leads down 3m to a deviation made by placing a loop over a large stalagmite. There may still be loose material in this shaft. It soon widens out into a 32m drop onto a wide boulder shelf. A window ahead looks down on an almost circular shaft which is also gained either by climbing down large blocks or using a re-belay off the nose of a buttress. There are shafts and climbs along the opposite bearing that lead back toward the shafts below the entrance.
  From the bottom of the climb from the 35 m shaft a short 5m scramble leads down to an eye-hole into a 7m climb into a short boulder slope to a tight take-off on the next pitch with one spit. Rope access of 12m leads to a short passage that soon becomes too tight.
   Back in the entrance chamber on the opposite 81° bearing a short muddy slope below the ladder has a Y-hang to a 18m pitch below a large jammed boulder into a three-way chamber. On the 250° bearing a short climb leads to the head of a wet 12m pitch to a boulder strewn floor. Climbs over large blocks reach the shafts seen from the opposite side below the 32m shaft.
  In the other direction from the base of the 18m pitch a short climb down leads to the start of a traversable rift. A hole to the right at this point is a dog leg leading to a parallel rift which, after 10m or so, gets too wide to traverse and was disto pinged to 12m depth. There is a continuation beyond this which appears to lead to a further shaft which is undescended. This does not appear to connect back to the parallel rift or shafts and needs a short traverse line rigging to see if it opens out or continues.

Continuing across the traversable rift a bridge is reached from where a series of three Y hangs lead to the top of the 13m third pitch, which lands on a ledge which is the start of the fourth pitch, again 13m. The landing leads immediately to the fifth pitch which pinches in to a small rift in the floor and has been distoed to 24m.

At the top of the fifth pitch it's possible to look along and down the rift to a ledge below in an undescended parallel shaft, which has also been distoed to 24m. Stones thrown at this ledge continue dropping beyond the ledge for some distance. It appears that this shaft can be reached by descending the fifth pitch part way and then a traverse would need to be rigged.

The lowest point shown on the current survey (24/10/2011) - point 15 - is the top of the fifth pitch, at -64m. Adding 24m for the fifth pitch takes the cave to -88m (or 70m altitude) and, as stones are dropping below this level, it would appear that the cave is dropping to around 60m altitude or lower. Assuming that Aguanaz is the nearest resurgence at 50m, should there be any horizontal development, El Suto could be significant in that it could be potentially give us access to a new system to the northwest of Aguanaz.

  The big shaft is reached by hanging a rope from a series of 3 Y-hangs, the drop from the last being an estimated 15m to a ledge where the other side of the rift slopes to meet the base leaving a shaft 1 m under the right wall. The base of the shaft pinches in to a small rift in the floor. Stones dropped from above suggest that it opens out below the pinch with an estimated depth of at least 20m. Hence the estimated depth from the first Y-hang is 5+15+15+20 = 55m.
Therefore the estimated total depth at 29-04-2011 is 13+18+55= 86m.
A G Latham and Phil C Goodwin. Additions T Brocklebank.

A survey was started in the summer 2011. Batches 11-01 and 11-02 have been drawn up and await further surveying. (Length 139m; depth 64m)

The site was totally (?) (re-)surveyed in April 2023, giving a final depth of 84m and 216m length.
The following description of the entrance and the Right Hand (East) Series is by members of the Imperial College Caving Club:

   If parking by the small inlet opposite the field, walking diagonally across the field bearing slightly right rapidly brings you to the start of the relevant path, starting at the tree line. About 50m down this path, a pothole is found 5m to the left of the path.
    Previously filled with a selection of large tyres that have been hauled out to clear the entrance, the entrance pitch is a ~15m spiralling slope, to be rigged by a 22m rope. The topmost attachment point is the nearby tree, which provides two anchors. There are two deviations on the way down - one from a spit (from previous expeditioning) and one from a newly bolted through bolt, both about 3m apart. Just before the final drop a through-bolted rebelay provides a clean drop to the tyre-filled chamber.
    Here there are two ways down - one directly behind where the rope drops down (the 'left route'), and one down a small climb to the top of a pitch (the right route). The left route has two spits of questionable vintage which was left undescended by ICCC in 2023. A long traverse line was rigged from the middle of the chamber down the climb leading to the right route until the pitch head was reached. This traverse passes some pretty formations, and the top of the pitch head is also well decorated.
    Here a Y-hang of new through bolts drops was bolted in 2023. A long deviation was rigged off of the large stalagmite to allow a clean drop all the way to the bottom of the chamber. This is a ~30m drop, lined with fragile formations and various nooks and crannies along the walls.
    At the bottom of the pitch, there is a small inlet that leads away from the drop which quickly chokes and dies, despite looking to be a connection on the original survey.
    The obvious way on down a ~15m climb was rigged with a loose traverse line, leading to a squeeze at ankle height that opens up into a 3m drop. The small chamber that this drops into contains a false floor, and a small crevice on the right hand side leads to the final pitch. This squeeze is slightly tighter than the previous, and quickly opens out to a 5m diameter, 15m deep pitch.
    At the bottom of this, a crack in the wall appears to lead on to a passage below, however is too tight to be passable by any reasonably sized human. If this were to be widened, it is possible that the passage below continues, as there is no end visible from the chamber.

The final pitych in the Left Hand (West) Series was also dropped to an end with no leads. It is suggested that there may be a traverse over the top of the pitch to a continuing horizontal passage. There could also be another similar lead higher up the cave.

Reference: anon., 2010c (summer logbook); Corrin Juan, 2011; anon., 2011b (Easter logbook); anon., 2011d (summer logbook); anon., 2011e (autumn logbook); anon., 2023b (Easter logbook)
Entrance pictures: summer 2010 : Easter 2011 : Easter 2023
Underground pictures : Easter 2023
Video :
Detailed Survey : projected section sketch from 2011: 2023
Line Survey :
On area survey :
Survex file : 2011 (Amended magnetic declination December 2013 to align with Eur79 grid and coordinates altered to fit ETRS89 datum, April 2014.) : 2023