They once carried an iron-plate bridge westward across the low ground, connecting to a long iron trellised span that cleared the river itself before climbing to a limestone bluff on the eastern bank. The line is long gone, lifted after closure in 1967, but the stonework remains, sitting in agricultural land beside the ruins of Carrigabrick Castle, quietly outlasting the railway it was built to serve.

The bridge was part of what became known locally as the Duke's Line, so called because its construction was funded almost entirely by the Duke of Lismore. Built by Bagnell and opened in 1872, it was operated from the outset as an extension of the service running north from Mallow under the Great Southern and Western Railway. The route connected into the broader rail network of the region, serving the Blackwater valley until the Waterford, Dungarvan and Lismore Railway took over the line in 1893. That company ran it for the better part of the following century before closure came in 1967 and the track was subsequently removed. What remains is the masonry, limestone blocks with a rock-faced finish on the five surviving piers, built to carry weight that will never return to them.