Tresviso Caves Project

Tresviso Caves Project Gazetter

PO-40: Torca de Trasdeltoyu

East, North:357323, 4792399 (nearby)
Coordinate Quality:GPS
Long, Lat:-4.7581845384282, 43.270870671464 (map)
Elevation (m):1202
Length (m):168
Depth (m):-30
Active Lead:
Survey Available:


The Trasdeltoyu Torca, with its two entrances, is located in the central area of ??the Trasdeltoyu lapiaz. This lapiaz is intensely developed. A powerful fracture of the rock mass, causes the main entrance to be intuited (PO-40). The secondary mouth (PO-41) is hidden behind a large pinnacle of rock, making it more difficult to locate


No description currently available


From the main entrance, and after a vertical of 4 m we will be in a room with a slight downward slope. When advancing a few meters the inclination is accentuated, and the dimensions are reduced. A steep, narrow passageway leads to a low ceiling room and abundant formations. At the side of the room a meander through which an active watercourse flows, offers two continuations.

Upstream, and heading south, we will advance between formations. After a narrowing between columns, the meander is transformed into a large and comfortable conduit, through which the active course runs on one side. When it reaches a point where the duct is occupied by a large column, the same loses amplitude, until it becomes a narrow meander where the water reaches through an impenetrable duct. An easy climb puts us in a short stay on the active course. At one end of it, a 4m well allows us to return to the active course, however, it reaches again through a narrow impenetrable duct, where it will be impossible for us to continue. This narrow pipeline suggests a possible continuation. Forcing this step is a task to be considered in future campaigns. Returning to the room described above, and to follow the active downstream, heading north, we will have to descend a small vertical of 3 m. Here, the duct has more comfortable dimensions. Within a few meters, this conduit ends up becoming a spacious room. This room is travelled through the active course, until it is added at one end of it, between blocks and sediments.

At this point the -20 m depth is reached, and this is where we can see how a ray of light arrives from the ceiling. The well that forms the PO-41, 10 meters from its descent, climbs the aforementioned room, offering a second entrance to the cavity.

In the room where we are, and at its west end, we find a well 12 m deep and 4 m in diameter, with its base completely flooded, and with no possibility of continuation. The cavity, at this point, reaches its maximum depth with -30 m.

Returning to the entrance well, near its base and on one side, we find a narrow passage between blocks, which allows us to access a horizontal gallery with several collapses, and a clear North direction. Walking through this gallery without difficulty, we reach a point where the same one makes a shaft, at an angle of 90 degrees, to the east. From here, with a steep incline we can descend to -21 m deep. Finishing the cavity, with no possibility of continuation.

The Trasdeltoyu Torca (PO-40 + PO-41) reaches a maximum depth of -30 m, with a total development of 168 m. Exploration completed.


Club d'Espeleologia l'Avern,2018


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