2025

Abstract

The 2025 expedition continued with ongoing exploration in Andara (Eastern Massif) of the Picos de Europa, Northern Spain.

Summary

The main objectives of the 2025 expedition were:

1. Cueva del Nacimiento – Exploration at the far end, ends at an obvious large rift, along a main fault, with multiple ongoing leads.  In 2023 a major chamber was found ‘The Shepton Mallet Matador’ and several promising black spaces in the floor of the chamber were identified. Although heading back down, rather than out to the surface, given the distance still to go to the deeper potholes, going back down seems to be the better option for finding a continuation of a trunk route into the mountain.

2. Cueva de la Marniosa –Sump 2 was passed in 2018 to a small pitch in an ongoing streamway.  This was subsequently dropped and quickly encountered sump 3.  A dive of the sump was planned for 2025.

3. Torca del Picu Boru (Flowerpot) – last visited in 2018 a return is planned to this -723m deep system and most likely a feeder into Cueva del Nacimiento

4. C29 Torca Brana Espina – First discovered in 1973, down to 110m and a sump, this was extended in 2023, by draining the (perched) sump and progressing to nearly -450m depth down a series or large pitches, very similar to a Yorkshire pothole. At the bottom the cave has entered a well-developed rift series, slowly turning and heading towards Cueva de la Marniosa. The cave sits between the deeper Andara caves at the top of the mountain and the Cueva del Nacimiento resurgence. It could be a vitally important piece of the cave development picture.

Results:

Cueva del Nacimiento – Barbenheimer & the Shepton Mallet Matador

The far end of Nacimiento once again provided unwilling to give up any major secrets.  Barbenheimer (North) was pushed through a series of tight squeezes, a smoke bomb test underground was possibly detected, via smell, on the surface and a radio location test confirmed the location on the surface.  A climb near the Matador chamber continues and more leads remain.  This is another site that is becoming increasingly difficult to explore, due to the distance from underground camps, so further satellite camps need to be considered in the future.

Further resurveying in the cave has also been uncovering more new passage, and the ongoing resurvey of the whole cave is slowly piecing this together.

Cueva del la Marniosa – Sump 3 and new inlets

The cave between Sumps 1 and 2 were re-rigged to make safer and the following day a team of 2 dived through to Sump 3.  The diver subsequently kitted up with 1x3L and 1x2L cylinder and entered the sump. The passage was quickly seen to descend, through dark limestone, to -11m at 27m distance, with minimal change in direction (heading SE), and further steps down to -14m at 36m distance.  A gravel floor was soon met which started sloping gradually upwards, however the diver met thirds at -12m at 51m distance and turned around, surveying on the way back. 

The sumped passage continues directly towards Nacimiento. However, this probably marks the end of exploration beyond the sumps for the present time.  The difficulty and remoteness of the site makes future dives incredible difficult logistical challenges.

Torca del Picu Boru (Flowerpot)

The drafting climbs identified on previous trips proved to be nothing but more of the same rift.  Further trips pushed slightly further into the cave, passing a notorious tight restriction to a series of large chambers and pitches, not visited since the 80’s and marked with a lot of dotted lines on the old survey.  This will be examined further on future trips for possible high-level ways on.

Cueva C29 (Torca Brana Espina)

C29 has a sump approx. -120m down, which needs to be draining before exploration can be undertaken.  This failed in 2024, so it was only this year that a return to the cave was attempted.  The limit in 2023 at -450m was ongoing in horizontal rift passage.  A trip was undertaken to ‘finish’ off the cave… but unexpectedly a way on was found that popped out into a large streamway!  Huge downstream and upstream leads were pushed for over 1km with ongoing passage in both directions and multiple inlets entering the streamway.

Members

Documents & Links

Tresviso 2025 30 MB 140 downloads

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Ghar Parau Tresviso 2025 Summary Report 2025 1.8MB 45 downloads

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