In writing of Sharpsburg there are particular features of that battlefield to which reference must frequently be made in order to comprehend the struggle, and these will first be noted.
The town of Sharpsburg is about a mile from the southward bend of the Potomac. A straight line running due east from the Potomac and passing through Sharpsburg would cross the Antietam river about 1 1/2 miles from the town. The general direction of the Antietam in front (east) of Sharpsburg is a little west of south. And this, too, is the general direction of the Potomac in the vicinity of the battlefield. About 3 miles below Sharpsburg the Potomac makes a sweeping bend to the east and the Antietam to the west, the latter entering the former just below the point where the river turns sharply to the south. Lee's line was in front of Sharpsburg and behind the Antietam, which was easily forded, and crossed by good stone bridges in Lee's front and on each flank.
Two main roads gave direction to the battle, one running north to Hagerstown, and the other a little north of east to Boonsboro. About 1 1/4 miles from the town, on the Hagerstown road, was a church known as the Dunker's
