Antietam National Cemetery is located in Sharpsburg, Maryland, and was established in 1865 to honor the soldiers who fought in the Battle of Antietam during the American Civil War. The cemetery contains the graves of over 4,000 Union soldiers, many of whom were killed in the battle on September 17, 1862, which was one of the bloodiest single-day battles in American history. The cemetery features a large monument, the Soldiers' National Monument, which commemorates the sacrifices made by the soldiers. Visitors can explore the well-maintained grounds, which include walking paths and historical markers that provide information about the battle and the soldiers buried there.