The Krakatoa eruption caused a devastating tsunami in 1883. The volcanic crisis began in May, but its catastrophic climax came on 27 August, when Krakatoa’s major explosions shattered much of the island in the Sunda Strait between Java and Sumatra.
The tsunamis were generated largely when enormous pyroclastic flows and collapsing volcanic material entered the sea. Waves reached about 42 metres along parts of Java and 24 metres along southern Sumatra. The town of Merak was destroyed by a wave reported at roughly 46 metres.
More than 36,000 people died, most from the tsunamis rather than the initial explosions. The event is sometimes confused with the 1815 eruption of Mount Tambora, another Indonesian volcanic disaster, but Tambora’s main legacy was a global climate shock and famine rather than Krakatoa’s famous tsunami.