One of the strongest series of earthquakes ever to hit the United States happened not in Alaska or along California's San Andreas fault, but in southeast Missouri along the Mississippi River.

 

In 1811 and 1812, the New Madrid fault zone that zig zags through five states shook so violently that it shifted furniture in Washington, D.C., and rang church bells in Boston. The series of temblors changed the course of the Mississippi River near Memphis, and historical accounts claim the river even flowed backward briefly.

Geologists consider the New Madrid fault line a major seismic zone and predict that an earthquake roughly the magnitude of the Haiti earthquake (7.0 on the Richter scale) could occur in the area during the next 50 years.