A French count and a Spanish bishop disagreed over who should rule a small rural enclave high up in the Pyrenees. They decided to rule jointly, and the result was the Principality of Andorra, the only country in the world whose official language is Catalan.
Nowadays it's not so rural but its spectacular scenery makes a great base for a ski holiday or a multi-activity summer experiences..... and duty-free beer/perfume etc is great for the budget. But if it is of interest (as we are)it is also possible to appreciate the odd bit of historical interest.
<For Foreign Office Travel Advice on this destination - see FCO advice