Six million homes and businesses in Spain are to get fibre to the home (FTTH) over the next four years.
The roll-out by Vodafone and Orange will see the pair expand their FTTH footprint to 50 cities by 2017.
While there's no word yet on the sort of speeds the fibre will deliver or where it will be available first, Vodafone has confirmed it will start to become commercially available from January next year.
The first 800,000 premises will get FTTH by March 2014, rising to three million by September 2015. When the deployment is complete in 2017, it's expected to cover 40 percent of Spanish premises.
Orange and Vodafone will spend €1bn between them on the roll-out, which will see them share street-level fibre. Each operator will deploy and own the fibre separately in different areas, but will design their networks to be interoperable.
According to the Fibre to the Home Council, Spain's FTTH penetration is around two percent, roughly equal to a number of countries on the continent - including Italy and Finland – but far behind Europe's FTTH leaders Latvia and Norway, both with around 15 percent.
Overall fixed broadband penetration in Spain is around 25 percent, according to the most recent figures from the OECD.