When Vatnajokull, Europe's largest glacier, began it's retreat from the shore of south Iceland around 1950, it left behind a lagoon around 100 meters deep, filled with cold meltwater and huge icebergs that head out to the sea. The colors and shapes of the Jokulsarlon are astounding and a very poplar tourist attraction. Vast icebergs break off into the lake and drift around. The sand and gravel dunes all around are the main breeding grounds of the Great Skua in the northern hemisphere.