Part of the Linha Norte system of the national railway, the wrought iron, double-hinged, crescent arch spans , over the Douro River. At the time of its construction, it was the longest single-arch span in the world; today, it is no longer used for rail transport and was replaced by a modern structure in 1991. It is often confused with the D. Luís Bridge, which was built nine years later and is located to the west, but resembles the structure, albeit with two decks.