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The Hanging Bridge of Vizcaya
Monday, 01.07.2008, 04:27pm (GMT)
The Hanging Bridge of Vizcaya, crossing over the mouth of the Nervión River west of the capital of Vizcaya province, Bilbao, is a remarkable feat of engineering which was the first bridge in the world to carry both people and traffic on a suspended gondola, and is the only one of its type still in use today. Indeed, it was used as a model for many similar bridges elsewhere in Europe, as well as Africa and the Americas. Only a few of those bridges survive today.
This transporter bridge stretches up for 45 metres, spanning the 160 metres between the two banks of the Nervión – which is officially known today as the Ibaizabal – connecting the towns of Getxo and Portugalete.
The man who designed it, the Basque architect Alberto de Palacio, was given two main requirements: that it should be able to carry both cargo and passengers, and that it should not disrupt river traffic. He achieved that with crossbars spanning the river, riveted together in sections winched up from below by barge, supported on double towers on either side of the Nervión, with the whole structure anchored and stabilised by a system of twisted steel cables. It was also designed with a view to installing a passenger walkway and lifts at a later stage, which would not, in the event, take place until a century later.
The final stage was the gondola itself, a 10 x 5 metre construction suspended from the bridge above. It was originally constructed with a platform of timber planks, with separate sections for first and second-class passengers. The holders of the cheaper tickets were given only standing room and had to share their section with cargo and cattle. A second class passenger ticket at that time cost 5 céntimos, the same as for an ox or a mule.
Today’s prices are 0.30 € per passenger, or 1.10 € for a car, with a service which operates every 8 minutes and a crossing duration of a minute and a half.
The whole construction process had taken a little over three years from start to finish, from the start of excavations on the Portugalete Bank on 10th April 1890, to the inauguration of the Puente Colgante de Bizkaia on 28th July 1893.
The Infanta Doña Isabel de Borbón decided to stop in Portugalete when she was on an official visit to Vizcaya province less than two weeks after the bridge officially opened, and was so delighted with this new form of transport that she made six trips over the river.
The bridge has been in almost constant use ever since it was built, apart from a four year period which began during the Spanish Civil War with the order to destroy all forms of transport over the Nervión to prevent the advance of Franco’s troops. The explosives were set on 17th June 1937, and the crossbars fell into the Nervión below. Reconstruction started two years later, and the Puente Colgante opened again on 19th June 1941.
There was further restoration in the 1990s, when the gondola was replaced, with work on all the main parts of the structure, using original materials and techniques.
The bridge has its own website, www.puente-colgante.com, which notes a number of curiosities over the years: in 1912, a man known as the Human Kite, earned the princely sum of 300 pesetas when he jumped form the bridge, with his only safety measure a rope attached to the platform of the puente colgante. There was a suicide who amazingly survived the first two attempts and only died on the third, and a driver in the 1960s who accidentally hit the accelerator instead of the brake as he was driving on to the gondola and ended up in the river. He escaped unhurt, but it was a different story for his brand new car.
Today, the bridge is used by around half a million vehicles and six million passengers every year. It is listed as a cultural monument, and was granted status as a World Heritage Site in 2006 for what UNESCO described as ‘one of the outstanding architectural iron constructions of the Industrial Revolution.’ UNESCO’s Advisory Body Evaluation, in its statement of outstanding universal value, also noted the combination ‘of iron technology evolved for railways with the innovative technology of lightweight twisted steel cables’; the fact that it is the first hanging transporter bridge in the world; and ‘its marked impact on bridge construction around the world.’
The World Heritage Committee described the bridge when the Puente Colgante was added to the list on 13th July 2006, as a perfect combination of functionality and aesthetic beauty, in an exceptional expression of technical creativity.
Source : Typically Spanish
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