This is a complex work that serves the Bilbao metro and is made up of four significant parts: 1º) Bridge with a 70 m span over the river. 2º) Viaduct nº 1. 3º) Elevated station. 4º) Viaduct nº 2. All the structures have a double gauge track with all its services and, in addition, side platforms and a roof are added to the station, as well as the communication corridors, stairs, lifts and accesses. A box structure was also used to house a transformer substation and various equipment. In order to unify the different parts of the work and provide it with an element that makes its status as a metropolitan railway clear, metal arches were placed every three metres. These elements, which together give the impression of a vault, serve as a support for the catenary and the protective railing.