The Burnside Bridge, originally known as Rohrbach's or Lower Bridge, was built in 1836 by John Weaver at a cost of $3,200 as a crossing of Antietam Creek southeast of Sharpsburg. On the morning of September 17, 1862, the Union Ninth Corps, under the command of Maj. Gen. Ambrose Burnside, faced the daunting task of attacking Confederate infantry and artillery located on the far side of the Lower Bridge.
Topography at the site heavily favored the few hundred Confederates who defended it. The road approaching the east end of the bridge swung on a course paralleling that of Antietam Creek; in the last few hundred yards before reaching the bridge, the road plunged into a funnel-like depression between the opposing bluffs of the creek. Confederate troops were in rifle pits on the west bluff overlooking the bridge and the approach road.
Even with a numerical advantage, the difficult terrain and stubborn Confederate defense kept Burnside from capturing this critical Antietam crossing for three hours. After the Bridge was captured it took another two hours to cross the Ninth Corps and reorganize for the final attack on the Confederate right flank. The delay proved costly, as Confederate reinforcements arrived from Harpers Ferry just as the Federal assault was finally meeting with success. More than 500 Union troops had been killed or wounded attempting to carry the crossing, known ever since as Burnside Bridge.
After the battle, the bridge was actively used for traffic until as recently as 1966. In an effort to preserve the bridge, a bypass was built to take cars on to a new bridge upstream. Today, visitors can once again quietly stroll across what has become the icon of Antietam Battlefield. The peaceful, bucolic setting belies the terrible struggle that took place over 150 years ago.