The above photo is the back side of Bloody Lane at Antietam battlefield outside Sharpsburg, Maryland. During the noon hours of September 17, 1862, Confederate (South) forces used a sunken road to act as a natural trench against wave after wave of Union (North) attacks. It was not until the third assault that Union troops were able to outflank the defenders, and shoot down into the road. The sunken road, which was the protector of Southern forces, turned into a death trap. By 1:00 the road was full of bodies.
The sunken road provided a great blind spot for Confederate forces. While Union forces were forced to fight on top of the ridge in the background, exposing their full bodies, Confederates were mostly hidden. The above photo has a 6 feet 4 inches tall man standing inside the natural trench. Below is the same man standing outside the sunken road.