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Cabin John, Maryland

Union Arch Bridge

The bridge's controversial plaque (once again) honors Confederate President Jefferson Davis. 

Although at one time this masonry arch bridge outside of Washington, D.C. was the longest of its kind in the world, it has become better known for the controversial names on its dedication plaques than the engineering feats of its construction.

The Union Arch Bridge was part of the Washington Aqueduct, planned after a fire broke out in the Capitol building and there wasn’t a ready supply of water to fight it. The construction of the bridge began in 1857, and while this work moved along smoothly, there was no shortage of drama and political intrigue going on behind the scenes.

The Civil War broke out the year the bridge was completed. One of the primary architects of the bridge, Army Corps of Engineers officer Alfred Rives, resigned and joined his native Virginia in the Confederacy. The other, officer Montgomery Meigs, had his name removed from a dedication plaque on the bridge and replaced it with the Latin phrase “Esto Perpetua” or “Let it last forever.”

Another plaque commemorating the bridge listed the names of government officials who started the project and those in office when it was finished in 1861. However the Secretary of War when the project began was Jefferson Davis, who was now infamous as the president of the Confederacy. The decision was made to remove his name from the plaque as well.

By the early 1900s, however, Southern politicians began lobbying to have Davis’ name carved back into the bridge. Theodore Roosevelt, in one of his last acts as president, controversially ordered that Davis’ name be returned to its original place.

Although officially dedicated as the Union Arch Bridge, over time the bridge became more well known as the Cabin John Bridge, and was added to the National Register of Historic Places as the Cabin John Aqueduct. Whatever you want to call it, it was clearly constructed well, still carrying water to Washington, D.C. from the Potomac River, as well as vehicle traffic the engineers couldn’t have anticipated.

Know Before You Go

The one-lane bridge is on MacArthur Boulevard between Cabin John and Glen Echo. There is parking along the side of the road before and after the bridge.