After crossing over the river using the two Bolueta arch bridges, the Bilbao Underground crosses over the river yet again at a place close to the second bridge. The underground spans the river at this point on two superposed levels due to the fact that the Etxebarri garages lie on the left river margin, which requires a crossing on a different level. Therefore, we had to create a bridge made up of two platforms over the river, extended on either margin through approach viaducts.
