Curated OER
National Park Service: Antietam National Battlefield
The National Park Service offers a wealth of information on Antietam, the battle, casualties, flags, and weapons. A very worthwhile site.
Other
Antietam on the Web
A comprehensive resource from Antietam on the Web of the Battle of Antietam, including historical documents, battle maps and much more.
Curated OER
National Park Service: Cwsac: Civil War Battle Summaries: Battle of Antietam
This site, which is provided for by the National Park Service, gives a brief overview of the events at the Civil War Battle of Antietam.
Library of Congress
Loc: America's Story: The Battle of Antietam
What was the bloodiest battle in all American history? The Battle of Antietam , during the Civil War, wins this dubious honor. The Library of Congress has more information about this famous battle along with some actual photographs.