The largest earthquake to ever hit Tennessee occurred in 1811, measuring a magnitude of 7.4 on the Richter Scale. The quake caused extensive damage throughout western Tennessee and was felt as far away as New York City. It caused the Mississippi River to flow backwards for over an hour and aftershocks could be felt for three weeks afterwards.
The 1811 earthquake remains the most powerful in Tennessee's history and caused significant damage throughout the state. The largest aftershock measured at a magnitude of 5.2 and was felt, along with numerous lesser tremors, in a wide area extending from New Orleans to New York City. The ground shook as far away as Cincinnati, Ohio and St. Louis, Missouri and ground waves were felt all throughout the Appalachians. In Memphis, chimneys were toppled and walls cracked during the event. Fissures opened in the ground west of Reelfoot Lake and large waves could be seen crashing against the shoreline for hours after the main shock occurred.