Situated amid the Bidasoa river bordering France and Spain,  the Pheasant Island switches its nationality every six months. According to a 350-year-old arrangement, representatives from France and Spain meet on the island every six months to exchange official documents and transfer ownership of the island.

Pheasant Island is a piece of uninhabited land with an interesting political and historical background. It served as the final battleground of the Thirty Years' War between France and Spain. With their respective forces positioned on either side of the Bidasoa, in case of negotiations failed, the two nations dispatched a few of their most significant dignitaries to the island.

An agreement was reached finally after 11 years and 24 summits, and Pheasant Island became the smallest condominium in the world i.e. the island is shared between the two countries, with control rotating from one to the other. 

It was an unusual end to a very long war. On the tiny island, French King Louis XIV wed Maria Theresa of Spain, the daughter of King Philip IV. Later, a monument honoring the historic agreement was erected in its center, and most importantly, it was decided that going forward, both countries would share custody of the territory for six months out of the year.

Ever since the historic agreement was made in 1660, Spain owns the Pheasant Island from 1 February to 31 July of every year and France controls it for the remaining six months. On rare occasions, like the bi-annual handover ceremony or on extremely rare heritage tours, visitors are permitted on the island.