Warsaw: A team of Polish and Czech explorers say they've discovered that a flooded abyss in the eastern Czech Republic is the world's deepest underwater cave at, at least, 404 metres.
Polish explorer Krzysztof Starnawski, who led the team, said on Friday he felt like a "Columbus of the 21th century" to have made the discovery near the Czech town of Hranice.
![A remotely-operate underwater robot, or ROV, searches the Hranicka Propast, or Hranice Abyss, cave's bottom, which it ...](/web/20161001060136im_/http://www.smh.com.au/content/dam/images/g/r/s/t/b/z/image.related.articleLeadwide.620x349.grstcm.png/1475282039011.jpg)
Starnawski and his team of scuba divers have been exploring the Hranicka Propast, or Hranice Abyss, since 2015, descending to more than 200 metres at a time. But on Tuesday, the team sent a remotely-operated underwater robot, or ROV, through a narrow passage into the limestone sinkhole from a depth of 265 metres. It went down to 404 meters, the length of its cord, but appeared not to have reached the bottom.
AP reported the Czech cave beats the previous record-holder, a flooded sinkhole in Italy called Pozzo del Merro, by at least 12 metres. The Czech Speleological Society said it believes the cave is even deeper and would yield additional records.
![Polish explorer Krzysztof Starnawski explores the limestone abyss before a deeper robotic exploration of the flooded ...](/web/20161001060136im_/http://www.smh.com.au/content/dam/images/g/r/s/t/b/w/image.related.articleLeadwide.620x349.grstcm.png/1475282039011.jpg)
The expedition, partly funded by the National Geographic, continues. Starnawski planned to dive to 200 meters again to bring the robot back through the narrow passage on Saturday.
AP