Take a peak inside Sweden’s longest underwater cave

Every winter, a group of hardy Swedes muscle their way on snowmobiles to Jämtland, a rural mountainous province in central Sweden. They call themselves Expedition Bjurälven and they have one goal: dive in the depths of Dolinsjö Cave.

Discovered in 1979, the cave is relatively unknown to explorers. That's the beauty of it. So far, the expedition has only reached a little over a mile into the cave. No one knows how much further they can go. No one could be more thrilled at the prospects than this bunch, many of whom dive hundreds of dives each year. "You can be absolutely sure that you are the first person to see this very room in the cave," says one member. 

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If diving into frigid, dark water (with no hot tub in sight, I might add) doesn't sound like your cup of tea, focus on the camaraderie. Like with any good outdoor expedition, these people are tight knit. They accept each other as they are and focus on pushing the boundaries of their sport, together. As another member says, "It's hard to explain to friends and family, who have a certain point of view of things, that you can't live on what every body else says. You need to listen to yourself, really." That rings true across all disciplines of adventure.