Krzysztof Starnawski/Krzysztof Starnawski EXPEDITION via AP/File
In this underwater photo taken in 2015 in the flooded Hranicka Abyss, Czech Republic, Polish explorer Krzysztof Starnawski is seen examining the limestone crevasse and preparing for a 2016 expedition to measure it depths. On Sept. 27, 2016 Starnawski and his Polish-Czech team discovered that the cave goes 404 meters (1,325 feet) down, making it the world's deepest known flooded abyss.

Czech Republic home to world's deepest known underwater cave

Czech Republic: An underwater cave found by Polish cave divers is called Hranická Propast. It was explored using an underwater robot. 

Explorers knew that the Czech Republic cave called Hranická Propast was deep. But until a team of spelunkers led by Krzysztof Starnawski delved deeper, nobody knew just how deep it was.

The team determined on Tuesday that Hranicka Propast was 1,325 feet deep, the deepest cave on Earth yet discovered. The previous record holder, a cave in Italy called Pozzo del Merro, was measured at a mere 1,286 feet deep.

To aid in their discovery, the team used a remote operated vehicle (or ROV) to plumb the cave’s darkest depths. Yet while explorers and researchers are increasingly finding ways to use technology for exploration, Mr. Starnawski says that robots don’t diminish the role humans play in discoveries like Hranicka Propast, but rather that they amplify it.

“Robots do not do the job instead of us. We, the humans, are still needed to show them where to go,” Starnawski told National Geographic, who partly financed the mission.

Divers have explored this particular cave for years - Starnawski himself has been diving there since 1999. Spelunkers say that the abyss is interesting to explore because of the unique method in which it was formed.

“This cave is very unique because it’s like a volcano, formed from hot mineral water bubbling from the bottom up, rather than rain coming from the top down like most caves,” Starnawski told National Geographic last year, when the team announced the cave’s potential depth.

“There are probably only three caves like this in the world. There is nothing typical about this cave, and every dive we make new discoveries.”

As a result, the cave includes tight bottlenecks, jammed with tree trunks and rock debris. Starnawski dove through one, located about 200 meters (656 feet), into the abyss beyond once in 2014. He was forced to spend six hours in a decompression chamber in order to recover from that dive.

After that, the team brought in the robots.

“My intention was not to achieve the deepest dive by a human, but to assist the exploration by the ROV. In this cave we wanted to explore beyond the 400-meter limit. It can't be done, so far, by a scuba diver in the cave,” Starnawski said.

The team obtained a robot from GRALmarine, and guided it down into Hranická Propast, to the depth of 1,325 feet where it ran out of rope. Starnawski plans to dive to the bottleneck, which the team calls “The Squeeze Passage,” TO retrieve the robot on Saturday.

Scientists are increasingly choosing to use robots to reach the depths of inner space (as well as outer space). In April, Stanford University researchers announced the development of a “robo-mermaid” with touch sensors that is able to delicately handle small objects, and allow underwater explorers to reach new deepwater shipwrecks and archeological sites.

What’s next for Starnawski?

The diver won’t stop seeking new depths, he told National Geographic last year.

“This cave is a big part of my life because I have been exploring it for 15 years, and it keeps going deeper. I want to show people that this is the deepest underwater cave. If I succeed, I will be fulfilled for a few minutes…then I will need to find a new project.”

You've read  of  free articles. Subscribe to continue.

Dear Reader,

About a year ago, I happened upon this statement about the Monitor in the Harvard Business Review – under the charming heading of “do things that don’t interest you”:

“Many things that end up” being meaningful, writes social scientist Joseph Grenny, “have come from conference workshops, articles, or online videos that began as a chore and ended with an insight. My work in Kenya, for example, was heavily influenced by a Christian Science Monitor article I had forced myself to read 10 years earlier. Sometimes, we call things ‘boring’ simply because they lie outside the box we are currently in.”

If you were to come up with a punchline to a joke about the Monitor, that would probably be it. We’re seen as being global, fair, insightful, and perhaps a bit too earnest. We’re the bran muffin of journalism.

But you know what? We change lives. And I’m going to argue that we change lives precisely because we force open that too-small box that most human beings think they live in.

The Monitor is a peculiar little publication that’s hard for the world to figure out. We’re run by a church, but we’re not only for church members and we’re not about converting people. We’re known as being fair even as the world becomes as polarized as at any time since the newspaper’s founding in 1908.

We have a mission beyond circulation, we want to bridge divides. We’re about kicking down the door of thought everywhere and saying, “You are bigger and more capable than you realize. And we can prove it.”

If you’re looking for bran muffin journalism, you can subscribe to the Monitor for $15. You’ll get the Monitor Weekly magazine, the Monitor Daily email, and unlimited access to

QR Code to Czech Republic home to world's deepest known underwater cave
Read this article in
QR Code to Subscription page
Start your subscription today