The Whistled language of Antia, also known as "sfiria", is a whistled language spoken by the inhabitants of the mountain village of Antia, in Evia (it belongs to the so-called "villages of Cavondoro" and it is 37 kilometers away from Karystos). In addition to Antia, whistle dialogues have also been recorded in Simikouki and Evangelismos villages. Each whistle corresponds to a letter of the alphabet and their composition leads to the creation of whistling words.
The media discovered the language in March 1969 when rescue crews tried to find the body of a pilot whose plane crashed in the area of Mount Ochi.
It is probable that the inhabitants of Antia were descendants of Persian soldiers guarding Greek prisoners in the Karystos area. After their defeat in the Battle of Salamis, the Persian army abandoned Karystos and fled to the highlands around Antia. They mixed with the local populations and assimilated them. Another theory states that inhabitants of Antia are of Doric origin, since they do not speak Arvanitic unlike the surrounding populations. Another version presents a group of residents of Ainos to be responsible for this dialect during their transfer to the area in 1469 as prisoners of the Venetians.
Whistle messages can be heard four kilometers away, that is ten times far away from a cry. The whistled language faces the risk of extinction in recent years and this is also confirmed by the Unesco Atlas of the world's most endangered languages.