The 1883 eruption of Krakatoa caused the Indonesian volcano to collapse into a caldera.
Krakatoa, also spelled Krakatau, was a volcanic island in the Sunda Strait between Java and Sumatra. Its major eruption began in May 1883 and reached its most destructive phase on August 27, when enormous explosions destroyed much of the island.
The eruption generated tsunamis that devastated coastlines around the Sunda Strait and killed tens of thousands of people. The final explosions were heard thousands of kilometers away and are often described as among the loudest sounds in recorded history. Atmospheric ash and aerosols also produced striking sunsets and temporary global cooling.
Much of the original volcanic structure collapsed below sea level, forming a caldera. A new volcanic cone, Anak Krakatau, later emerged within the caldera and became active during the 20th and 21st centuries. Krakatoa is sometimes confused with Mount Tambora, whose 1815 eruption was even larger and caused the “Year Without a Summer” in 1816.