Find out why Porto is known as the “City of Bridges”.
Get to know those who designed the bridges that link both sides
of the river and why they are considered part of the city’s
built heritage.
Ponte Pênsil
(Suspended Bridge)
This bridge was officially named Ponte D. Maria II (D. Maria II Bridge), never having been called by this name though. The engineers Mellet and Bigot were the ones responsible for the project, and the foundation stone was set in 1841. The bridge was open to public use in 1843.
The bridge had two 18m tall masonry obelisks on each side, on top of which were the suspension cables of the 6meter wide plate. The central span of the bridge occupied 150m of the 170m between the cliff of Guindais and the Penedo, in Gaia. The cables comprising 220 cords each, kept the plate at a distance of 10m above water level, being anchored in vertical pits of 8m on the side of Porto and 14 m on the side of Gaia. These days there are but two obelisks on the right bank of the river.
The first great piece of work by Gustavo Eiffel is double hinged arch that sustains the single lane railway plate through pillars to reinforce the whole of the bridge. The construction works began on 5 January 1876 and were concluded the following year on 31 November. The solemn inauguration ceremony took place on 4 November 1877 by the king D. Luís and the queen D. Maria Pia, after whom the bridge was named. This bridge was used for 114 years, until 1991, when the Ponte S. João (S. João Bridge) became active.
In accordance with the Law of 11/02/1879, the government determines the opening of the competition for the “construction of a metal bridge over the Douro River, in the place considered the most convenient in front of the city of Porto, for the replacement of the current suspended bridge”. The winning proposal was the project of engineer Teófilo Seyrig, from the Belgian company Societé de Willebroeck.
Teófilo Seyrig had already been the author of the plan and head of the team in the project of the Ponte D. Maria Pia (D. Maria Pia Bridge) as Eiffel’s associate. This time he was the sole responsible for this work of the new and grand Ponte Luís I (Luís I Bridge). The construction works began in 1881 and the inauguration occurred on 31 October 1886). The arch comprises 172m of cord and is 44.6m tall.
In March 1952, the Junta Autónoma de Estradas (Autonomous Highway Authority) passed judgment upon the elaboration of the sketch for the highway bridge to Professor Edgar António de Mesquita Cardoso, bron in Porto on 11 May 1913 and deceased on 5 July 2000.
The Ponte da Arrábida (Arrábida Bridge), which contains a 270m span, set the world record for concrete bridges for some time. The arch is 52m tall and the plate rises up to 70m above water level. The construction lasted from May 1957 to 22 July 1963, day of its opening.
Once again the responsibility of conceiving the project of a bridge was placed upon Edgar Cardoso. This time, the plan was to create a project for a railway bridge that would replace the old D. Maria Pia Bridge. This railway structure adopts a solution consisting of a portico with three spans (two measuring 125m and one of 250m), set upon majestic pillars founded at the riverbed, by each of the banks. The inauguration took place on 24 July 1991, S. João Day.
The Ponte do Freixo (Freixo Bridge), a work by Professor António Reis, consists of two twin beams, set apart by 10m throughout the whole of the extension. The bridge stands upstream of the other bridges, at the very edge of the city. The bridge has 8 spans, the main one measuring 150m. This one is followed by 115m spans on each side, which, in turn, are followed by minor ones. This bridge comprises 8 traffic lanes.
Ponte Infante D. Henrique (Prince Henry, The Navigator Bridge)
The Prince Henry Bridge was inaugurated in 30 March 2003 following a project by the engineer Adão da Fonseca. With a 371 metres long and 20 metres wide deck, it is a Maillart-type arch bridge, built at a high altitude level, presenting a span-rise ratio of 11,2, with a 280 m arch span – a world record, meaning that domains never entered before in this kind of bridges (considered by the world experts to be the most elegant) have now been achieved.
The bridge has two basic interacting elements: a box girder, relatively rigid, with a regular height of 4,5 m, supported by a flexible 1,50 thick arch with a 280 m span and a 25 m rise.
The bridge is a four-lane dual roadway, each of the lanes being 3,25 m wide. The safety of the traffic is reinforced by a 1 m wide central reservation.
The lighting is essentially functional and its placement on a low altitude level integrated in the parapets, in the structure of the jersey barriers and in the central reservation, allows a perfect light effect along the way, without disturbing the visibility or adding any unnecessary vertical shapes. The bridge is decorated with lighting under the arch just to spotlight its bottom by the slope and fading away in length.
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