The Bilbao metro was instituted to become the backbone, the coordinating axis of all means of transportation serving the Bilbao area and its environs.
Construction work on the Bilbao metro began in 1988 in Erandio. Afterwards, the first ground stone was laid in Plaza Moyua in March 1990, thereby initiating work in downtown Bilbao.

The first phase of Line 1, Plentzia-Casco Viejo, went into operation on November 11, 1995 leter on July 5, 1997 were inaugurated Santutxu, Basarrate and Bolueta stations, and work on the line was finished on January 8, 2005 with the inauguration of subway stations Etxebarri. Thus, a 29,27-kilometre long system with 28 stations between Plentzia and Bolueta, 13 of which are underground and 15 above ground, became fully operative.

The municipalities through which this first line runs are given below along with the number of stations located in each one of them:

• Bilbao: 11
• Getxo: 6
• Erandio: 3
• Leioa: 2
• Sopelana: 2
• Berango: 1
• Urduliz: 1
• Plentzia: 1
• Etxebarri: 1

This first line has brought about an improvement in mobility across the metropolitan area and has been able to turn around the trend towards heavier traffic that runs along the "Solución Sur and "La Avanzada".

The Metro has also resulted in more direct transformations such as bringing the Erandio, Las Arenas and Algorta stations underground which has done away with the barriers that the above ground train service posed and has allowed for these newly freed zones to undergo urban development.

Although indirectly, work on the metro has also allowed for a refurbishing of Lehendakari Agirre Avenue, the main thoroughfare running through the borough of San Inazio. Likewise, this has led to a car park with a 500-vehicle capacity to be built.
..
When the Metro went into operation, public transport capacity increased both quantitatively and qualitatively and thus there has been an ever increasing number of commuters. Indeed, approximately 32 million commuters used the service in 1996 and last 2002 the number nearly topped 67 million passengers, metro the opening of the frist phase of Metro Bilbao line 2.