5854258 Smithfield Street Bridge over Monongahela River, Pittsburgh, c.1968 (colour photograph) by American Photographer, (20th century); Private Collection; (add.info.: Southwest portal of Smithfield Street Bridge,Pittsburgh, Allegheny County, Pennsylvania for Historic American Engineering Record Designed by Gustav Lindenthal (using a double lenticular truss, patented in America by Edwin Stanley in 1851) as a two-lane bridge.); American, out of copyright.