This stone bridge across the Antietam Creek became a focal point of the fighting on the afternoon of September 17, 1862. Union troops commanded by General Ambrose Burnside struggled to cross the bridge. The encountered murderous rifle fire from Confederates on the bluff on the opposite side.

The bridge, one of three across the creek and known to locals before the battle simply as the lower bridge, would be known after the battle as the Burnside Bridge.

In front of the stone wall to the right of the bridge is a row of temporary graves of Union troops killed in the assault on the bridge.

The tree standing at the near end of the bridge is still alive. Much larger now, of course, it is revered as a living relic of the great battle, and is known as the "Witness Tree" of Antietam.