Discovery of the decade in the cave Sancinova jama

A discovery dedicated to the great caver Stojan Sancin - 2021-10

The karst area between Sežana and Lipica on the Slovenian side and Basovizza and Opicina on the Italian side is considered to be one of the most researched caving areas. Many generations of explorers and cavers have been for more than 180 years dedicated to finding entrances that would lead them to diverse caves, and even deeper to the mysterious underground river Reka. The stories that emerged during the research are still considered unprecedented in heroic deeds, and fortunately for researchers, not only stories but also infrastructure such as excavated tunnels, old ladders and fences, and kilometers of carved paths remain.

The most famous caves of the Trieste Karst are certainly Grotta Gigante (Briška jama), which is adapted for tourist visits, and the Grotta di Trebiciano (Labadnica). Both caves began to be explored as early as the middle of the 19th century because of the water supply of Trieste. In Grotta di Trebiciano, the river Reka was reached by a web of drops of various depths at a depth of 329 meters in the giant Lindner Hall, but in those times, water extraction from such depths was technically questionable and unprofitable.

The next huge cave in the area was reached by cavers only after 150 years later. In 1990, the Grotta Claudio Skilan (Skilanova jama) was discovered near the Slovenian-Italian border at the Lipica border crossing, which is the longest cave in the area with a length of over 6,400 meters and a depth of 378 meters. The cave is famous for its beauty and has everything a caver could wish for. Huge halls, beautiful stalactite decorations of all shapes and colors, ponds and pans with huge crystals. The book Taste of Darkness by Slovene writer and photographer Bogdan Kladnik was also published about this cave.

In November 2004 the next giant cave was accidentally discovered during the excavation of the tunnel of the new motorway connection above Trieste. During the blasting, workers came across one of the tunnels that converged into a huge hall measuring 130 x 80 meters, with a ceiling over 80 meters high. Due to a completely unexpected discovery, the cave was named the Grotta Impossibile (Impossible Cave). Later, cavers from the hall discovered new continuations and extended the cave to over 4.5 kilometers in length. The entrance to the tunnel was later closed by workers so the cavers had to find a new entrance. Under the ceiling of the great hall, they came across a web of tunnels that approached the surface only a few meters above, and from there, with the help of an avalanche beacon, they confirmed a new entrance and dug through it.

We had to wait until this year for a new big discovery. Claudio Bratos and Stojan Sancin (caving club Jamarski odsek SPD Trst) discovered a small gap between Basovizza and Padriciano 20 years ago, but left it for “some other time” due to other projects. Unfortunately, at the beginning of this year, due to Stojan’s death, their joint exploration ended. During this year’s area exploration, Claudio remembered the crack in the ground again and, together with caver Mauro Kraus (Gruppo Speleologico San Giusto), set about expanding it. The excavations began in August and, with the help of other members of the Mauro Society, progressed rapidly. At the end of October, they finally succeeded in breaking through. A wider abyss opened up, where only small crack prevented the continuation at the bottom, and after the strait the next level had already turned into the top of the hall.

The enthusiasm at the discovery was, of course, great and immediately spread throughout all the caving groups. It is not very often that such spaces are discovered in a carefully researched area, that can lead to a new “giant” of the Trieste karst. Claudio kept us up-to-date on his progress through the entrance straits via his YouTube channel and posted footage of walking around the Great Hall. Excerpts from this video were used in the first press releases, which was quite enough for the breaking news, but for a better display of the discovery, of course, we should have arranged it with real photos.

We stood in front of the entrance to the cave only a week after the discovery and admired the great work of the research team. The first excavations were carried out in a blow-hole 15 meters away, from which almost 10 cubic meters of soil and stones were dug up, breaking through more than 15 meters deep, but there the draft was soon lost and eventually completely disappeared. Therefore, they started digging in the second crack, where they soon noticed the lost draft, and later, due to the fluctuation of the draft, they discovered the connection between the two cracks.

Advancing through the second crack was much easier and therefore also faster. The tunnel is completely dry and clean until the entrance to the Great hall. Contact with mud awaits the caver only on the edge of the last drop in front of the Great hall, and if he is careful, he gets dirty only to a lesser extent or not at all. Every visit to the cave inevitably leaves traces, and the most visible and destructive are mud traces. Therefore, it is extremely important, especially in newly discovered caves, to take great care of their preservation for as long as possible.

The Great hall leaves no caver indifferent. The point where you descend into the hall is the top of a huge collapsed stone cone, from where a view of the entire hall opens. In the middle reigns a mighty group of stalagmites, surrounded by numerous speleothems, stalactites hang from the ceiling, and in the distance we can only guess the size of the chimneys that mysteriously lead to the unknown above. Every step around the hall is a walk on a flowstoned surface, intertwined with many crystals, pans and pearls, so choosing motifs in such an ambience is quite difficult. Every movement of the team has its consequences, and every responsible caver wants to keep those to a minimum.

The most beautiful part of the cave opens at the far end of the hall. Here we meet for the first time large calcite crystals and helectites, which with their eccentric shapes undoubtedly impress every caver. However, the largest specimens are found only in the lower-lying hall. Access to this hall unfortunately leads through a few meters of muddy drop, where the caver inevitably gets dirty. We had to end the visit here, as we had no spare footwear, and the muddy boots would leave irreparable marks on the way back.

A week later, we dedicated the second visit mainly to the details in the central part of the great hall and to the visit to the lower hall with helectites. With the spare footwear, we got rid of the mud problems and walked around the hall in a relaxed manner, carelessly devoting ourselves to unusual forms of helectites of various lengths. The discovery of beautiful crystal flowers, with a distinctive triangular central part, provided additional joy, and we made magical finale by photographing the entire hall with all the stalactite decorations in it.

Satisfied with unforgettable impressions and wonderful motifs, we also filled the second day well, but most of the work was, of course, still waiting for me by going through a large amount of photos. The motifs displayed on the screen testify to how wonderful the caves of this area were at the time of discovery and what fate may await them due to the reckless behavior of uncareful cavers through decades of mass visits. The researchers and the first visitors treated the cave with respect. We can only hope that times just change for the better and that the next cavers will also be able to appreciate and preserve the originality of the newly discovered caves. Sancin’s cave surely deserves it.

In Sancinova jama, we admired what we saw in two visits and at the same time tried to take photos Anja Kos, Janez Ferreira-Stražišar, Miha Staut, Ines Klinkon and Anja Hajna.


Copyright Peter Gedei