The "Silbo Gomero" (Whistled language)

A unique whistled language in the world, fully developed and practised by a large community (more than 22,000 people). It was awarded the UNESCO Intangible Cultural Heritage of Humanity designation in 2009.

It is practised in the island of La Gomera, one of the Canary Islands, and involves whistling in Spanish. It replaces vowels and consonants with whistling. Thus, two differentiated whistles replace the five Spanish vowels, and another four, the consonants.
The tone of the whistle and the interruption or continuity of the same is what tells each syllable apart. The whistled language can convey any message and even identify the origin of the whistler according to its local variant.

Almost the entire population of the island understands it and it is taught in the schools since 1999. That is why most of the people from La Gomera practise it, especially older and younger people. Likewise, the whistling is used in many festivities, including religious feasts in La Gomera.