Ziemlich abgefahrenes Ding - Höhlentauchen im Winter... nenee - nix für mich...
"The Dolinsjö Cave is a an underwater cave system that was discovered in 1979. Expedition Bjurälven is an annual expedition, exploring the depths of the cave. So far, the expedition has reached 1.7 kilometres into the cave, but noone knows how far it stretches."
Underground Movement: Cave Diving in Jämtland from Klättermusen on Vimeo.