Shepherds from the French Pyrenean village of Aas had their own language entirely composed of ear-splitting hundred decibel whistling. It could be understood at a distance of two miles away and was complex enough to communicate the contents of a newspaper.

It was used at least until the second world war when shepherds helped Jewish refugees, Résistants and stranded pilots cross the border into Spain.

Though older people today remember hearing the language they can't reproduce it and there are no known recordings :(