Hidden in the Jämtland Mountains of Sweden, a group of spelunkers and cave divers are exploring the Dolinsjö Cave, the longest underwater cave in the country. The exploration, started seven years ago by the Swedish Speleology Association, looks to find out just how far this cave will go, but due to strong water currents in the warmer seasons, they must dive in the depths of winter.
It’s this unique composition that brings more gravitas to what they are doing. Fighting physical and mental challenges in the name of science, each diver seems to nurture their own personal need to push the limits of human exploration. “For me, I live for diving,” said one of the divers. “I dive hundreds of times every year and it’s a special feeling when you get to go somewhere no one has ever been. You can be absolutely sure you are the first person to see this very room in the cave.” As of last winter, the team has explored 1.7 kilometers (one mile) of the cave, yet its total size remains unknown.