Between 10 September and 2 October 2011 an international caving expedition took place in the area of Radohines peak (2570 m), North Albania.
The main purpose of the expedition was to explore the depth of the abyss Ru, initially discovered by Bulgarian speleologists in 2010. A year latter Ru is the cave with the deepest cascading pit of -320 m in Albania. Ru is the second deepest cave in Albania -550 m (with the bottom still unreached), second only to BB30 with its -610 m.
The first 300 meters of the abyss Ru are vertical well, which follows the underground structure of one of the faults. There are no intermediate thresholds and stone blockages. The breadth of the well varies from few meters up to 25 m. In some sectors along its vertical axis there are connections to neighboring wells with similar structure. At -350 m the character and appearance of the cave change. There comes a zone with narrow passages which require lots of efforts from the cavers. A zone with meanders follows.
New areas were discovered all the time; on the very last day of the expedition 80 meters long meander named “Hope for all” was traversed and additional 100 meters depth were discovered. The cave continues so new expeditions are planed and brand new discoveries are expected. Thus far a map of the cave down to -461 m is ready.
The expedition gathered biospeleological samples of the animal species in the cave, which are currently studied by the National Museum of Natural History of the Bulgarian Academy of Science. Two samples of probably brand new species Hirudinea Indet were collected from a pond at -420 m in the cave, which were send for study in Slovenia. Other important invertebrates are the Macrochaetosoma troglomontanum, which is endemic for the region and has been found also in the cave Maja Arapit (part of another massive in the Albanian Alps, not far from Radohines). Larva of Colembolla, (genus Onychiurus) were found crawling on the walls of the first 100 meters, and also a representative of the insects – Family Curculionidae Indet, which was probably accidentally there. The biospeleological explorations are due to continue during the future expeditions.
During the expedition another 11 caves in the Radohines peak area were discovered, marked and studied. Their depth is between 20 and 50 meters and in nine of them the bottom (an ice cap or rock block) was reached. One of them – Ledenata (The Icy) was explored down to -130 meters, yet no bottom was reached. Its exploration will be the goal of next expeditions.
A film for the expedition was made „Dreams of Stone – the Prokletia underground”. Its premiere was during the celebration of 20 years of Bulgarian speleo explorations in Albania and was latter screened during several festivals dedicated to speleo and alpine adventures.