Five days and 116 years ago, a small island in the Sunda Straight between Java and Sumatra exploded.
They heard Krakatau go bang in Perth, Australia. And 4,600 km to the west they heard it too, on Rodrigues Island in the middle of the Indian Ocean. The airwave it created hit Bogota, Colombia, on the other side of the world 19 hours later. It then bounced, back and forth, seven times. Krakatau's 40-meter-tall tsunami killed 40,000 Javans and Sumatrans, drowned one person in distant Ceylon and hit Le Havre, France, 32 hours later. (By that time, the killer wave was just 1 cm in height.) Sunsets around the world were extravagant with light flamed by floating ash for weeks afterward.
Krakatau was not the biggest volcanic eruption in human history. In 1815, the Tambura eruption on Sumbawa Island (also Indonesia) lifted "five times the rock and ash," according to Harvard biologist E.O. Wilson's magnificent book, "The Biodiversity of Life." And 75,000 years ago, an eruption in central Sumatra (Indonesia again!) punched out an impressive 1,000 cubic km of solid matter. There's a lake there now.