Sharpsburg and Antietam National Battlefield are accessible only by car, although once you're there, the village itself is very easy to cover by foot. Sharpsburg is located on MD-34, which connects with US Interstate 70 via MD-64 and US-40.
The Battle of Antietam
The Battle of Antietam was the bloodiest day in American Military History. 23,000 soldiers were killed, wounded or missing after twelve hours of savage combat on 17 September 1862. The Battle of Antietam ended the first Confederate invasion into the North and led to Abraham Lincoln's issuance of the preliminary Emancipation Proclamation.
The Battle of Antietam was the culmination of the Maryland Campaign of 1862, the first invasion of the North by Confederate General Robert E. Lee and the Army of Northern Virginia. Following a defeat at South Mountain, General Lee considered ending his campaign in the North and withdrawing to Virginia, but upon hearing of General Stonewall Jackson's victory at Harpers Ferry, he decided to make a stand at Sharpsburg.
The Confederate commander gathered his forces on the high ground west of Antietam Creek with Gen. James Longstreet's command holding the center and the right while Stonewall Jackson's men filled in on the left. Union General George McLellan focused the Union forces upon the left flank of the Confederate Army along the Sunken Road, and hammered away in brutal stalemate. Union General Ambrose Pierce led the planned assault upon the Confederate right flank seven hours into the battle, after General Lee had already transferred many troops to the left flank, but was held up in capturing the bridge that bears his name by a small Confederate force from a higher defensive position. After taking the bridge, General Pierce paused for two hours to reorganize his forces, delaying his assaults upon the Confederate right flank. By the end of the day, General McLellan's assault had failed to break either flank, leaving a large portion of his central forces out of play, leaving the brave efforts of his men in the fight nullified by his overly cautious assault. General McLellan left the battle embarrassed and in poor standing with the President. The tactical stalemate remained, both armies were decimated (nearly 1/4 of the men fighting), and Sharpsburg was nearly destroyed. General Lee, seeking to avoid a drawn-out battle of attrition with the larger Union forces, withdrew across the Potomac, ending his strategic campaign in the North.
This bloody battle, despite the underwhelming tactical performance by Union generals, marked a strategic turning point for the North, as General Lee would from this point be forced to fight on Confederate soil. Perhaps even more importantly, the "victory" here gave President Lincoln the opportunity to make his Emancipation Proclamation, thereby making the war no longer just an attempt to restore Union sovereignty over the South, but a greater cause of ridding the United States of the evil practice of slavery. This gave the Union an important boost in morale, and helped keep foreign powers leery of supporting the cause of slavery from aligning with the South.