The Battle of Natural Bridge was a battle during the American Civil War, fought in what is now Woodville, Florida, near Tallahassee, on March 6, 1865. A small band of Confederate troops and volunteers, mostly composed of teenagers from the nearby Florida Military and Collegiate Institute that would later become Florida State University, and the elderly, protected by breastworks, prevented a detachment of United States Colored Troops from crossing the Natural Bridge on the St. Marks River. The Natural Bridge is a one-quarter mile long stretch along which the St. Marks River runs underground, after dropping into a sinkhole. This action prevented the Union Army from capturing the Florida capital and made Tallahassee the only Confederate capital east of the Mississippi River not to be captured by Union forces during the war. The battle has been described as the last Confederate victory in the American Civil War, and it was the second largest American Civil War battle in Florida.