There was constant disagreement between the inhabitants and the local politicians of the Aspe Valley with regard to the construction of the Somport road tunnel. The construction project for the building of the Somport road tunnel began officially in January 1994 as a result of the international agreement signed by France and Spain on the 25th of April, 1991. It was inaugurated nine years later, on the 18th of January 2003 by the Spanish Minister of Public Works - Francisco Alvarez Cascos, the European Commissioner for Transport – Loyola de Palacios and the President of Aragon – Marcelino Iglesias. There was no municipal representation from any of the towns and villages in the Aspe Valley.

The 8,608 metre tunnel was subject to improvements and increases in security measures during its construction due to the accident in the Mont Blanc tunnel in 1999. The excavation of nine evacuation galleries, one every 400 metres, eight of which connect directly with the railway tunnel, together with the existing security recesses, shelters, laybys, closed circuit televisions, etc., make this tunnel one of the safest in the world.

The building on the French side, known as the “French Entrance Building” is situated in Les Forges d’Abel, very close to the French mouth of the Somport railway tunnel. It is a secondary Operations and Maintenance centre. At present it is still unfinished but it is due to have three floors and 1045 square metres of useable space. It will have a secondary control centre, a ventilation station, a power station for providing and transforming eletricity and a pumping station for the French firefighting system.