Overview
What Krakatoa is
Krakatoa is a volcanic complex rather than one simple cone. Its geography includes caldera collapse, islands, volcanic deposits, and renewed cone building.
The record is useful for explaining how volcanoes can rapidly alter coastlines and island form.
Caldera
Collapse, remnants, and rebuilding
Explosive eruption and collapse created a disrupted volcanic landscape. Later activity rebuilt new volcanic land inside the same island system.
Collapse
Caldera structure
Large-scale failure reshaped the volcano.
Islands
Remnant terrain
Fragments preserve the older volcanic system.
Arc
Sunda setting
The volcano belongs to an active island arc.