Flowing river inside a glacier cave, Vatnajökull, Iceland

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Ice, ice, caving. Glacier cave in Iceland

The land of fire and ice is home to countless natural wonders, like these brilliant blue caves formed within the ice of a glacier. (Glacier caves are often called ice caves, but the latter term is properly used to describe bedrock caves that contain year-round ice.) Most of these glacier caves are on the southeastern edge of Iceland in Vatnajökull glacier, which covers about 8% of the island nation and is one of the largest glaciers in Europe.

Vatnajökull’s caves, formed by the flowing rivers underneath the glacier, are famous for their blue corridors and eerie atmosphere. The caves are only accessible from November until March when temperatures are cold enough to strengthen the ice. The caves vary in size and shape each year, so enjoy the beauty of this one while you can, because it may not be around next winter.