Things to do in the Santorini caldera

The caldera is the collapsed crater at the centre of Santorini, roughly 12km by 7km, with an inner cliff rising 250-300m above the water. It formed in a single catastrophic eruption of the Late Bronze Age, around 1600 BC, though the exact date is still debated between radiocarbon and archaeological evidence.

What you see from the rim terraces is that event's aftermath: the drowned crater, the two black islets of Nea Kameni and Palea Kameni that grew back from later eruptions, and the pale rock of Aspronisi. No lava is visible today, and the volcano last erupted in 1950, so this is a page about reading the geology, not watching it happen.

Boat trips into the caldera, some stopping at the islets, run most of the year and typically last 4 to 6 hours.