Vizcaya Bridge straddles the mouth of the Ibaizabal estuary, west of Bilbao.
It was designed by the Basque architect Alberto de Palacio and completed in 1893.
The 45-m-high bridge with its span of 160 m, merges 19th-century ironworking traditions with the then new lightweight technology of twisted steel ropes.
It was the first bridge in the world to carry people and traffic on a high suspended gondola and was used as a model for many similar bridges in Europe, Africa and the America only a few of which survive.
With its innovative use of lightweight twisted steel cables, it is regarded as one of the outstanding architectural iron constructions of the Industrial Revolution.
5 beautiful photos.