Tresviso Caves Project

Tresviso Caves Project Gazetter

T173: Torca del Cueto de Los Calabreros

(Dossers Delight, Bloques Deliciosos, Arch Pot, Bridge Pot)

Area:Pico Boro
East, North:359759, 4786831 (nearby)
Coordinate Quality:GPS
Long, Lat:-4.7267630439987, 43.221211964872 (map)
Elevation (m):1685
Length (m):1264
Depth (m):-831
Active Lead:
Survey Available:


North of Pico Boro there is a large depression below a small peak (spot height 1788m). In the centre of the depression is a ridge of rock on which the entrance is to be found. The entrance is a boulder lined funnel with a rock bridge.


obvious natural entrance with rock bridge

2022 - Entrance appears to be now blocked with a large boulder


The first pitch is at the bottom of the boulder funnel, the 12m Spider Pitch. This lands on a rubble slope, which leads to a 3m climb down into a large rift. The second pitch, 25m, is immediately on the left and has one bolt change (ed.1986) before landing on another steep rubble slope.

The next pitch takes off beneath a large poised boulder and is 34m, the Ore Chute. Climbing over this boulder leads to a short inlet passage with a small stream and pool. At the bottom of the pitch is another steep slope of boulders which ends in a very small slot.

However, just before this, it is possible to climb up on the right into another passage. Here a +9m climb / pitch ascends, the 1st bolt climb, leading into a narrow and jagged passage with boulder obstacles. This is where the next pitch of 50m, Very Vulnerable, takes off. This leads down between two parallel walls less than 2m apart, through several slots, then to a 7m pitch, to the head of If You Wanna go to Pittsburg Baby. This is a magnificent 43m pitch in a large shaft. Water enters at the bottom of Pittsburgh.

From one of the slots above the Pittsburgh Pitch, a traverse can be followed to several short pitches eventually meeting a stream which cascades down into the Pittsburgh shaft.

The water flows into a rift. Right leads to a dripping aven (unclimbed), but the way on is to the left, where the tortuous rift is best followed by crawling. After passing through a chamber and a series of traverses, The Bus is met, a superb 51m pitch, with a rebelay on a ledge half way down. The landing is in a circular pool, with the water running into a tight winding rift. Above this fissure an ascending traverse, Loo Nasty, is followed, finally traversing horizontally towards a 15m pitch. From the bottom a short traverse leads to the P37, which although awkward at the top is a fine shaft, again landing in a pool of water. More traversing and an awkward bend descends to a narrow slot, The Riddler. This leads to the P28, in another large shaft. From the bottom the rift can be followed at several levels, all leading to a massive calcite choke. Up the calcite slope is the 22m 2nd bolt climb, which although having a fixed rope on can be hung free at the top by hanging from the right, with a deviation half way.

At the top, right leads to a pool whilst left leads to a climb down to a 4m pitch, tight at the top. Beyond is Dossers Despair, an awkward descending squeeze straight onto a 9m pitch. From the bottom, traversing up leads to an 11m pitch at the base of which is an awkward crawl leading straight onto another P11. Below is a short climb to the last P4, the end of the Indelible Escalator. (approx. -310m)

Traversing forwards, a slot distends to a large passage leading on to the head of Murder Most Foul, a superb 70m pitch split by a ledge 23m down. From the base an ascending traverse leads to a thrutch and a 3m climb, to a tight rift and a P5 to Mutiny, a grand 41m shaft. By descending the canyon at the bottom, two short pitches are met, P5 and P6. At the base of the last one a climb to the left leads to a short, tight thrutch directly onto a P3. Immediately beyond is The Bounty, a magnificent 62m free hang. Yet another traverse leads upwards to the Camp site, extremely muddy and cold. (approx. -480m)

Beyond camp is a split P26 - One Step Beyond. From the base a P7 leads to the start of The River, the streamway which marks the change in character of the cave. Awkward going leads to the double pitches of Glory Days, P8 and P10, landing on a slippery boulder slope in a chamber. The lower end of this passes an inlet from an aven on the left (unexplored?), and descends into a high narrow rift with climbs leading to a 6m damp pitch, The Natural Thing. Similar passage drops to a deep pool formed by debris collapse, which it is possible to negotiate dry (just!) into an enlargement.

Climbing up below the previous pitch and a traverse lead to the same point. The water exits in a narrow tortuously spiky rift from where Paganuzzi's poo-poo Promenade leads off as an abandoned phreatic passage

Paganuzzi's Poo-poo Promenade starts as a traverse over the streamway leading to a T-junction in a big phreatic tube. Left leads back in a loop, whilst to the right further traversing/walking leads to a climb down into a chamber. Across this the passage continues big to a large stalagmite column. Beyond a tricky climb down around a car sized boulder is a large descending tube floored by a river of pure white calcite. Gradually the passage gets smaller from where a short crawl leads down the rift to a short drop to a ledge overlooking the stream at Thunder Down Under.

Following the water leads after two small pitches of 6m and 2m to the split pitch of Thunder Down Under (a P27 and P25). This can be rigged dry by traversing over the top in a dangerously loose old phreatic passage, dropping to a ledge, then by a rebelay to the floor starts as a large passage which continues.

From the chamber at the base of Thunder Down Under the stream drops over a short 2m drop into a chamber leading onto Pozo de los Picos. An 80m pitch is rigged dry from a shale slope on the right, dropping after a rebelay into a high narrow rift landing on a large balcony, with the water cascading over the edge in a further drop.
Continuing straight down Pozo de los Picos leads to a small boulder choke(?) and the water drains away. (Not confirmed, no description - worth a look?)

The far side of Pozo de los Picos shaft would appear to continue, leading away from the shaft. Possible enterable from the balcony and climbing up.

Back at the balcony in Pozo de Los Picos, climbing over a lip leads to a further 40m pitch separated from the water by a rib of rock and landing in a high narrow rift. The water is reached by climbing through a hole in the dividing rib, cascading from the pitch, and running into a small impassable hole.

The main passage continues in the same line as the pitches to a climb down into a chamber. The stream then runs into a slot, where a traverse reaches a pitch of 9m to regain the water in a continuation of the rift. Here the rift has mud covered walls and leads around a corner to a small pool, Fool Aussie Sump, which it is possible to traverse over. Just beyond the roof comes down to a definite blue/green sump pool of restricted size. (-831m)

Just after the 9m pitch, a traverse up the right wall reaches a series of holes, one of which drops back to the stream, the other two entering water filled epi-phreatic chambers without any discernible outlet. The roof between the large pitches and the 9m pitch is probably over 30m high, with possible alcoves, but would require aid to reach.


Caves and Caving no. 15,
Caves and Caving no. 28,
Caves and Caving no. 31,
Caves and Caving no. 37.
LUSS (1980). "Tresviso '80".
Anon (1981). "Cave descriptions and surveys. Dosser's Delight". En "Tresviso '81". L.U.S.S. 27 pags.
Daykin, K. (1982). "Tresviso '81". Caves & Caving-15:16-18.
Sefton, M. (1984). "Cave explorations around Tresviso, Picos de Europa, Northern Spain". Cave Science vol. 11-4:199-237.
Jones, H. (1985). "Tresviso 84. 56 and the year of the dosser".Caves & Caving-28:21-25.
Ibberson, P. (1986). "Tresviso '85. The year of the Dosser". Caves & Caving-31-14-17.
Barlow, C. (1987). "Tresviso '85". Australian Caver-112:23-27.
McKee, H. and Nicholas, T. (1987). "Tresviso '86". Caves & Caving- 37:28-29.
Ibberson, P. (1987). "Exploration of Dossers Delight, 1984-1985". LUSS-4:56-59.
Broughton, R. (1987). "Exploration of Dossers Delight, 1986".LUSS-4:59-62.
Anon.. (1987). "description of Dossers Delight". LUSS-4:63-67.


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