The World's Loudest Sound

The sound made by the Krakatoa volcanic eruption in 1883 was so loud it ruptured eardrums of people 40 miles away, traveled around the world four times, and was clearly heard 3,000 miles away.
Think, for a moment, just how crazy this is. It's like being in Boston and clearly hearing a noise coming from Dublin, Ireland. Traveling at the speed of sound, it takes a noise about 4 hours to cover that distance. This is the most distant sound that has ever been heard in recorded history.