What is the most famous tornado?

The most infamous tornado in U.S. history occurred on March 18, 1925. The tornado, which started in Reynolds County, Missouri, became known as the "Tri-State Tornado" because of its massive effects on Missouri, Illinois and Indiana.

The Tri-State Tornado, which lasted for three hours, set U.S. records for distance and speed. It also set records for number of deaths and amount of destruction caused by a tornado. The 695 deaths attributed to this tornado are more than double those caused by the second-deadliest tornado, as of 2014. The Tri-State Tornado was part of a larger storm system in which several other major tornadoes appeared.