Scientists have discovered the world’s largest underground thermal lake in a huge cave in southern Albania.

Researchers from the Czech Republic first uncovered the cave four years ago but did not have the correct resources to measure it at the time.

However, the team has now announced that they returned to the lake in 2024 – along with state-of-the-art 3D scanners – and have been able to confirm that the huge body of water is in fact the biggest of its kind known to science.

The lake measured at 454 feet long and 138 feet and has been named “Neuron”, after the foundation funding the expedition. 

Cave explorer Marek Audy said: “In order for Czech Science to present this phenomenal discovery, it was necessary to conduct scientific research and precise measurements.”

It was while exploring the border region between Albania and Greece that Mr Audy, along with his colleagues, first found the hidden chamber. The region between the two countries have been subject to political tensions for over a century and therefore has been off limits for some research. 

When exploring the area around Albania’s town of Leskovik, the team noticed a huge column of steam from a mountain range. When making a closer investigation, they saw it was rising from an abyss over 330 feet deep, the cave explorer revealed.

The researchers then went down into the bit and discovered a broad system of caves, including some with thermal springs and one containing a vast lake.

Richard Bouda, photographer and expedition member, told Euronews: “During our initial exploration, we created a basic map using our equipment and immediately realised that we had discovered something extraordinary.”

With funding from the Neuron Foundation, the team were able to use a mobile LIDAR scanner, which enabled them to measure the entire cave and lake area. Additionally, they used the latest scanning technology, including the GeoSlam system – a 3D scanning method that generates precise models of cave formations.

The incredible discovery is expected to have significant impact on hydrological and geological studies in the region and Richard Bouda shared that further research will offer a better understanding of the connections between surface and undergound water sources.