Explorers have found an underwater cave near the Czech town of Hranice that is believed to be the deepest anywhere in the world.
Polish explorers dove 200 meters down into the Hranicka Propast and released a robotic device that went down to a depth of 404 meters (1,325 feet) and still didn’t hit bottom, according to The Associated Press.
Team leader Krzysztof Starnawski told the AP Friday he felt like a “Columbus of the 21st century” after the discovery.
In 2015, Starnawski had dived to a depth of 265 meters without reaching bottom but suffered ill effects from the dive. To go deeper, the robot was needed.
The previous deepest underwater cave was the Pozzo del Merro in Italy at 392 meters.
Starnawski’s dive was partially funded by National Geographic, which first reported the record. Starnawski spends two to four hours in an underwater decompression chamber each time he dives into the cave at a depth of 200 feet, National Geographic reported. He said he likes to read special books with laminated pages while he waits underwater.
The explorer has been diving in Hranicka Propast for 20 years and still hasn’t yet reached the bottom of the cave.
The depth of 404 meters was as long as the robot could dive on its existing cord. During previous dives, hot water containing carbon dioxide bubbled up like a volcano. The water made any exposed skin itch. The bubbling water and its warm temperature suggest the cave could extend downward a great distance, Starnawski said.
It wouldn’t be possible for a diver to reach a depth of 404 meters with the current equipment available, so Bartlomiej Grynda from GRALmarine used his custom-built ROV to explore the depth of the cave beyond 200 meters.
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