Sfyria is a language (based on spoken Greek) which uses pitches,frequency and lengths of whistles from the "speakers". It originated about 2500 years ago on the island Evia (aka Euboea) in Greece. On the island rests Antia, a small village on Mount Ochi, where some of the inhabitants still use sfyria.

Developed millennia ago, it is a language that travels over great distances and allowed farmers and shepherds to communicate as the sound of the whistles echoes off the mountains. Whistling allows the sounds to travel 4 KM, about 10 times further than shouting.

Sfyria comes from the Greek word "sfyrizo", meaning ‘whistle’ to communicate. The distinct language was not "discovered" by the outside world until 1969, when a plane crashed in the mountains behind Antia. The search teams heard the strange whistles from the shepherds in the area and realized they were communicating to each other based on pitch, frequency, and lengths of the whistle blares.

Sfyria is one of the most endangered languages with estimates of less than 10 remaining humans whistling the unspoken language.

More Info: www.bbc.com