Union Soldiers of the Boston Light Artillery Posing With Their Guns in a Fortified Battery Overlooking the Thomas Viaduct in Elkridge, Maryland (1861)

Union soldiers of the Boston Light Artillery posing with their guns in a fortified battery overlooking the Thomas Viaduct in Elkridge, Maryland, 1861. The Baltimore and Ohio Railroad ran across the viaduct which was part of the only railroad connection into Washington, D.C., during the Civil War.

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