Public domain
Potomac Creek bridge - Acquia (i.e. Aquia) Creek Railroad built by U. S. M. R.R. construction corps in nine days from standing timber
From the collection of Library of Congress. Free to download, adapt and use — no permission needed.
Credit linePotomac Creek bridge - Acquia (i.e. Aquia) Creek Railroad built by U. S. M. R.R. construction corps in nine days from standing timber. 1861-01-01. Russell, Andrew J.. Civil War Glass Negatives, Library of Congress. Public domain.