Looking down what became known as Bloody Lane, a sunken farm road at the Antietam battlefield Confederate soldiers hid in this trench and decimated Union solders as they charged their position. It became known as Bloody Lane because of the horrific number of casualties inflicted in this spot. The Battle of Antietam, fought on September 17, 1862, was the bloodiest day not only of the American Civil war but of any American war. It was fought outside of Sharpsburg, Maryland along Antietam Creek and ended Confederate general Robert E. Lee’s first invasion of a northern state. The battlefield itself is considered the best-preserved of all Civil War battlefields.