Public domain
R. R. (i.e. Railroad) bridge across Bull Run. O. & A. R.R.
From the collection of Library of Congress. Free to download, adapt and use — no permission needed.
Credit lineR. R. (i.e. Railroad) bridge across Bull Run. O. & A. R.R.. 1861-01-01. Civil War Glass Negatives, Library of Congress. Public domain.