It shattered the eardrums of sailors over 50 kilometres away, sent shock waves around the world several times over, and could be heard by 50 geological locations covering over 10% of the globe. This was the loudest sound in recorded history occurred in 1883. The sound was caused by a record-breaking volcanic eruption that sent smoke up almost 80 kilometres into the air as ash fell into the ocean some 20 kilometres away. Burning hot debris was shot from the mouth of Krakatoa's volcano at speeds of up to 2,575 kilometres per hour, which is more than double the speed of sound.

The video below gives you an idea of what an erupting volcano sounds like, but of course, nothing close to what was described above!

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