On 7th November 1659, putting an end to thirty years of war between Spain and France, the Treaty of the Pyrenees was signed on  Faisans Island, at the mouth of Bidasoa river. Despite several advances, it will take two centuries to draw the border’s boundaries between both countries. Today, 602 milestones or crosses establish the current border from Hendaye up to Cerbère.

Following long negotiations, on the occasion of the Treaty of the Pyrenees signature in 1659, Spain gives up several territories to France, including in the Pyrenees Roussillon, Conflent and Cerdanya. 


But it was not until 1856 and the signing of the treaties of limits, known as the Treaties of Bayonne (1856, 1862 and 1866) that the border between the two states is taking shape, although some challenges still persist today.

The current border does not follow the ridgeline, but takes into account the many disputes that existed in valleys.

Among these anomalies, the Western border with its long enclave on the Spanish side; in central Pyrenees, the Val d’Aran, former dependence of Comminges county, now belongs to Spain; and finally the northern half of Cerdanya is joined with France, despite the direction of the watershed line.

Also worth noting that the cities of Puigcerda and Llivia became Spanish enclaves on French territory, just like the Quint Country in the Basque Country.

Among other originalities, in Perthus, the border runs through the middle of the street, with the left pavement in France and the right one in Spain!

Numerous agreements have been concluded between breeders' communities on each side of the valleys to allow herds “to enter to graze and drink freely on each other  territory, only remaining there during the day, from sun to sun”.

The 602 milestones establishing the border are checked by a demarcation delegate,  appointed by the French President.