The debate is not final, but quite some geologists and archeologists think that Santorini, or a part of it, was the old Atlantis. Or at least it is agreed that it is a good candidate for the title. The disappearance of Atlantis would coincide with the Minoan eruption, about 3,600 years ago and the collapse of the caldera, which you still can see today.
More about this place of interest
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