A souvenir half dollar was designed by William Marks Simpson and struck in 1937 to commemorate the 75th anniversary of the famous Civil War battle to thwart Lee’s invasion of Maryland. The opposing generals McClellan and Lee are featured on the obverse, while the Burnside Bridge, an important tactical objective, is shown on the reverse. The Battle of Antietam, on September 17, 1862, as one of the bloodiest single-day battles of the war, with more than 23,000 men killed, wounded, or missing.