Santorini caldera

Submerged caldera in the Aegean Sea

The Santorini caldera is a large, mostly submerged volcanic caldera located in the southern Aegean Sea, 120 kilometers north of Crete in Greece. Visible above water is the circular Santorini island group, consisting of the main island of Santorini (known as Thera in antiquity), Therasia and Aspronisi at the periphery, and the Kameni islands at the center. It has been designated one of the world's sixteen Decade Volcanoes.

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