Matka Vrelo reaches 338 m — deepest cave dive yet, system continues downward

An international diving team from North Macedonia, Poland and Italy has pushed Matka Vrelo to a new limit: a human explorer reached −338 metres during an expedition held between 10 and 17 October 2026, and the passage continues deeper.

Record dive and unexpected passages

Polish diver Bartolomej Pitala described the moment he went beyond previously known depths: "I felt great. I had no vision problems, nor did the gas density give me difficulties. But the drop kept going down. A few seconds later I reached −315 metres. Matka Vrelo became the deepest underwater cave ever explored by a human diver, and the passage kept descending steeply." At −338 metres he decided not to push his equipment further: "The passage still continued sharply downward. The way was unequivocally open. At that moment I was the deepest-diving person on Earth."

The team says the final plunge lasted nine hours and was supported by twelve divers positioned at different depths and time intervals. Preparations took six months, and organisers deployed more than 30 cylinders with different gas mixes across roughly ten locations, plus spare batteries for heating and lighting. For the first time the local club assembled and installed an air chamber (habitat) at 8–9 metres depth, positioned about 130 metres from the cave entrance, to support long decompression stops.

Matka Vrelo has climbed from its earlier position among the world’s deepest underwater caves. Last year the same system had been explored down to −287 metres; earlier milestones include Luigi Casati’s 212 metres in 2009 and Krzysztof Starnawski’s 242 metres in 2017. "This is how our cooperation actually began. With 'Vrelo 2026' we entered a new, critical phase of exploration, with club 'Vrelo' again hosting the Polish divers led by Bartolomej Pitala. With last year's achievement Vrelo stood third in the world by depth explored by a human," said Hristijan Milanoski from club "Vrelo".

Besides the record depth, teams from Poland and North Macedonia discovered two previously unknown channels that altered the system map. According to the expedition, in addition to the newly reached 51 metres of depth, more than 100 metres of new passages were explored — about 150 metres of previously uncharted cave in total. "We met all expectations. We carried out further surveys and mapping of channels totaling about 150 metres, and we mapped the greatest depth measured so far by a human — 338 metres. That way we placed Vrelo on the global speleological map as the deepest underwater cave examined by a human," said Goce Dimitrievski of club "Vrelo".

Local team member Slobodanka Jakimovska stressed the significance of the new passages for understanding the underwater system: "In cave diving these new channels are of exceptional importance because of the complexity of the overall underwater cave system." The expedition reported the first new channel lies about 300 metres from the entrance at a depth of 33 metres and is roughly 100 metres long; the second channel appears at 170 metres depth, is about 30 metres long and rejoins the main conduit at 185 metres.

Support measures included a hyperbaric medical team on standby, the Ministry of Interior helicopter unit, SAE "Tigar" personnel with fast boats and emergency medical services. Two weeks before the expedition an overhang of rock near the cave entrance had to be cleared by divers from club "Vrelo" and the Serbian club "Vidre" to allow safe access. Divers warn that beyond 300 metres the main hazards are decompression sickness and pressure-related neurological symptoms, and current commercial diving equipment cannot be guaranteed beyond about 350 metres, limiting how far human explorers can safely go for now.

After all members returned safely, Pitala shared the story of the operation on social media. The team says that although they set multiple records — deepest underwater cave explored by a human, deepest cave dive and deepest open-water dive — the greatest question remains: where the cave actually ends. "The feeling is doubled. Not only because of reaching 338 metres, but because the knowledge that the cave still has not revealed its bottom," the team commented.

Photo: press material from the event