Tambora’s eruption began on April 5, 1815, and did not stop until July.
Troops who were sent to investigate the early rumblings believed the sounds came from pirates attacking military bases.
The worst came on April 11 and 12, and the volcano’s explosions could be heard 1,000 miles (1,600 kilometers) away. Darkness fell at noon up to 300 miles (480 kilometers) away, a result of airborne volcanic ash and debris.
The following year, known as “the year without summer,” the effects of Tambora reached the northeastern United States and Western Europe. Crops failed and livestock died due to the intense cold. In the northeastern United States, snow fell all summer.
Famine threatened the Northern Hemisphere—all because of a volcanic eruption in Indonesia.
Volcanologists believe that Tambora’s eruption could easily have been the worst in 10,000 years.