Maria Pia Bridge

The Maria Pia Bridge is a railway bridge built in 1877, and attributed to Gustave Eiffel, situated over the Portuguese northern municipalities of Porto and Vila Nova de Gaia.Part of the Linha Norte system of the national railway, the wrought iron, double-hinged, crescent arch 353m spanned connected 60m 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 located 1km to the west, but resembles the structure, albeit with two decks.HistoryAt the end of the 18th century, the use of cast iron began to replace laminated steel on rail bridges, making it essential for the expansion of the rail network. In addition to permitting creative uses, due to its characteristics and new materials, the materials allowed the ability to overcome difficult terrains. Although developments in England were pioneering, it was the bridge conceived by Gustave Eiffel for the Bordeaux in 1860, designed by La Passerelle, that became the model of various projects. Similar to other European bridges, the development of modern bridges in Portugal accompanied the growth of transport networks, during the Fontist politics of the middle of the 18th century Regeneration period. The first metallic bridge in Portugal, the Ponte Pênsil, was constructed over the Douro, due to the commercial activities of British merchants between the two riverbanks. Meanwhile the extension of the Linha Norte to Devezas did not support the commercial interests of Porto and Gaia.