Illustration showing the possible shape of Santorini before and after the eruption of 1470BC. Santorini is an island in the Aegean Sea, about 100 km north of Crete. Positioned near a destructive plate margin, the island probably looked like the frame at left, with a central large volcano. This volcano suffered a catastrophic caldera collapse in 1470 BC, similar to but much larger than the explosion of Krakatau in Indonesia in 1883. All that is left today is a small ring of islands. It is possible that a Minoan city state on the island, destroyed in the eruption, was the basis for the legend of Atlantis.