TIL of Silbo Gomero (informally called Silbo), a whistling language originating from La Gomera, part of the Canary Islands under Spanish rule.

Silbo language in action here.

While the community of La Gomera speak Spanish, **Silbo **is a required subject for La Gomera students, and considered a Masterpiece of the Oral and Intangible Heritage of Humanity by UNESCO. They had to resort to such communication as the terrain (mostly ravines and valleys) usually made direct, face-to-face communication inconvenient and impractical. Think of it this way: going to your neighbor the next mountain over for some juicy Maritess

Absolutely fascinating language based on sounds alone!