A cave diving expedition earlier this month in Sweden’s Bjurälven Nature Reserve has further increased the length of Sweden’s longest underwater cave. Located in Jämtland mountains in northern Sweden, Bjurälven Nature Reserve is Scandinavia’s biggest area of karst topography.This year’s Expedition Bjurälven, held almost annually (only one year missed) by the Swedish Speleological Society’s Diving Section since 2007, saw some 20 members spend eight days exploring the Bjurälven river which disappears underground for about three kilometers (1.86 miles). Due to a strong summer rate of flow that make diving impossible, expeditions to the cave are only attempted in the wintertime when the flow is almost nonexistent. However, winter provides its own obstacles for divers including over a meter of ice and snow and freezing surface temperatures around -20 Celsius (-4 Fahrenheit). |