Which mountain chain runs along the border between France and Spain?
France–Spain border France–Spain border The France–Spain border was formally defined in 1659. It separates the two countries from Hendaye and Irun in the west, running through the Pyrenees to Cerbère and Portbou on the Mediterranean Sea. The Franco-Spanish border runs for between southwestern France and northeastern Spain. It begins in the west on the Bay of Biscay at the French city of Hendaye and the Spanish city of Irun (). The border continues eastward along the Pyrenees to Andorra (). At this point, the small country interrupts the border between Spain and France for 63.7 km on the Spanish side and 56
France–Spain border with the signing of the Bayonne Treaties between 1856 and 1868. During the mandates of the Queen of Spain Isabel II and French emperor Napoleon III between the two countries were signed several agreements by which the border was established: Later both countries concluded agreements under the same point. In 1980 an agreement was signed to define the border into the Bielsa-Aragnouet tunnel, and 1984, during the construction of the road linking the Roncal Valley with Arette, it was agreed a mutual transfer of land of 2710 m. In 1995, with the entry into force of Schengen Agreement, border controls