The Coraopolis Bridge is a girder bridge over the back channel of the Ohio River connecting Grand Avenue on Neville Island to Ferree Street in Coraopolis, Pennsylvania. It opened in 1995 to replace a structure of historic significance. The original Pratt/Bowstring/Pennsylvania through truss spans, designed by Theodore Cooper, were formerly the (third) Sixth Street Bridge, spanning the Allegheny River, in downtown Pittsburgh, and were built in 1892 by the Union Bridge Company. They were floated downstream by the in 1927 rather than being demolished when the bridge was removed to enable construction of the present (fourth) Three Sisters (Pittsburgh) Sixth Street Self-anchored suspension bridge. However, by the late 1980s, the old bridge could no longer support traffic volumes and was repla