Length: 385.25 m (1264ft)
Weight: 3045 tons (3356 tonnes)
Height: 44.6m (146.3ft)
Arch: 172m (564ft)
Like the Colosseum is to Rome or the Eiffel Tower is to Paris, the Ponte Dom Luís I is the symbol Porto, Portugal. Luís I Bridge in English, is a metal arch bridge which spans the Duoro river in northern Portugal. Stretching 172m (564ft) the bridge links the cities of Porto & Vila Nova de Gaia and at the time of its construction the longest bridge of its type in the world.
In 1880 the Porto council organised a competition for a tender to construct a double-deck metal bridge across the river Duoro. Tenders were received from engineers including the Frenchman Gustav Eiffel and John Dixon from England. The award, however, was given to Théophile Seyrig who represent the Belgian company Société de Willebreok. Seyrig was already known to the Portuguese as he had worked previously on the Dona Maria Bridge, also located in Porto, which was designed and built by Gustav Eiffel.
Construction began in 1881 with the upper deck being opened on the 31st October 1886 and the lower deck in 1887. On November 1, 1886, a toll system was introduced which was operated by the Société de Willebreok to cover the cost of construction. The tolls continued until 1944 and since then the bridge has been operated free of charge by the Porto Municipal Council.
Originally, and for more than a century, the bridge carried road traffic on both the upper and lower decks. From 1908-1959 trams crossed the upper deck and trolley busses crossed both decks from 1959 to 1993.
By 2003 the upper deck had been closed to all road traffic as it became part of the Porto metro system. This change eventually lead to the lower deck being enlarged in 2006 to cater for the increase in road traffic.
The main arch of the bridge spans 172.5 m (564ft) and supports both the upper and lower decks. The arch, and conversely the decks, is moored to the riverbank on masonry piers. Both decks are asphalted as well as being flanked by pedestrian walkways which are protected by cast iron guard rails