City and seat of New Madrid County, southeastern Missouri; population (1990) 3,400. The city lies on the Mississippi River where it forms the border with Tennessee, 77 km/48 mi south of Cape Girardeau. It was the scene of a major earthquake in 1811 (measuring more than 8 on the Richter scale), which largely destroyed the town and changed the surrounding landscape.
New Madrid is situated at the top of New Madrid Bend, where the Mississippi River, at one of its widest points, curves almost 360°. The city originated as a fur-trading post, established in 1783 by French-Canadian trappers, and was settled by American pioneers six years later. It grew rapidly until the earthquake, after which it became depopulated, as tremors continued for over two years and people fled. The town was moved at least three times before the Civil War. During this conflict, because it stood at a strategically important position on the river, it was occupied (1861–62) by Confederate troops under George Hollins and successfully besieged (1862) by Union forces under John Pope. Today, as throughout its history, New Madrid's main economic activity is marketing and distributing local agricultural produce. In 1990 a serious earthquake was forecast for the area, but did not materialize. The New Madrid Fault, a seismic zone some 192 km/120 mi long that caused the 1811 earthquake and many other smaller incidents, extends northeast to the Kentucky border near Cairo, Illinois, southeast across the Mississippi River into Tennessee, and southwest to a spot near Marked Tree, Arkansas. Negligible earthquakes occur almost weekly somewhere in the zone.