International Pastures. On the 13th of July every year, the Stone of San Martín, between the Valleys of Roncal and Baretous, bears witness to and plays a major role in a unique, age-old ceremony held in a natural setting of extraordinary beauty: the oldest international treaty still in force in Europe.

At the event, the inhabitants of the Bearnese Valley of Baretous, dressed in suits and bearing the French flag, hand three cows, all with identical horns, coats and teeth, over to the Roncal villages of Isaba, Urzainqui, Uztárroz and Garde as part of an enduring, annual tribute. Before they do so, the authorities from each side of the border place their hands on the Stone of San Martín and promise that peace shall continue to reign, an undertaking which is sealed when the Mayor of Isaba places his/her hand on top of all the others and pronounces the words “Pax avant, pax avant, pax avant”.

The origin of and reason for this ceremony are unknown. We know that the tribute was not paid in the 14th century, leading to a serious conflict between those living in the two valleys involving deaths and extremely unpleasant scenes. This all came to an end with a sentence pronounced in 1375 ordering the inhabitants of Baretous to continue to pay the Tribute. The sentence, in addition to being the first documentary reference available regarding the ceremony, also tells us that the tribute was already an established practice in 1375.

As for the causes, some historians, basing themselves on the perpetual nature of the Tribute, defend the hypothesis that it is, in fact, a tribute of war and not actually a form of compensation for the use of pastures and springs as popularly, and mistakenly, believed.