September 17, 1862. The Battle of Antietam is the costliest day of the American Civil War, and the costliest day in American history. Sharpsburg, Maryland is a small town in western Maryland. Robert E. Lee has set his men into the West Woods, the Sunken Road, and above the bluffs overlooking the Lower Bridge (Burnside's Bridge). Lee's Army of the Northern Virginia is outnumbered over two to one. McClellan arrives, the Army of the Potomac arriving east of Antietam Creek. McClellan moves Hooker and Mansfield's Corps over the creek. Hooker's Corps starts the push at 5:30am. Doubleday, Meade, and Rickett's Divisions advance along the Hagerstown Pike and East Woods toward the Dunker Church. The center of the landscape is dominated by a large cornfield. Jackson's Corps holds positions in the West Woods, East Woods, and Cornfield. The Union advances, but is countered by Hays' Louisiana Tigers. Then Hood's Division strikes. Hood pushes the Yankees back to the starting point. Mansfield's Corps now strikes. Greene advances on the Dunker Church, but is held in check without further support. The battle now shifts to the Confederate center at the Sunken Road. The rebels wait behind entrenched lines. French's Division approaches but is held back. However Richardson's Division will break the Sunken Road. Caldwell's Brigade angles into the entrenchments from the flank, and the rebels pull out. In the afternoon, Burnside finally moves his men over the Lower Bridge now called "Burnside's Bridge." Burnside's Corps advances toward Sharpsburg, but AP Hill's Division arrives just in time to throw it back to Antietam Creek. Music Credit: Atlantis by Audionautix is licensed under a Creative Commons Attribution 4.0 license. https://creativecommons.org/licenses/by/4.0/ Artist: http://audionautix.com/ Book Sources: "Antietam" by Gallagher Images from the Library of Congress Satellite images from Google Maps Film by Jeffrey Meyer