The 22st edition of Bulgaria's largest and most impressive Kukeri event – the Surva Festival – kicked off in the western city of Pernik on Saturday.

Hundreds of kukeri, or mummers, practitioners of a beloved Bulgarian folklore tradition with roots from Ancient Thrace, have gathered for the weekend event.

Together with numerous international representatives of festival cultures around the globe, the participants of this year's Surva Festival amount to 6,100.

They will have processions in downtown Pernik on Saturday and Sunday.

Henk van der Kroon, president of the Federation of European Carnival Cities, has announced that he has presented his collection of nearly 100 official medals as a gift to the city of Pernik, of which he is an honorary citizen.

The Surva Festival is in an ongoing procedure for inclusion in the UNESCO Intangible Cultural Heritage list, and UNESCO representatives are also in the western Bulgarian city.

Numerous members of the international diplomatic body in Sofia were also present at the festival launch Saturday.

The Kukeri rite is performed in Bulgaria between Christmas and Lent by costumed men with animal masks who walk around and dance to scare away the evil spirits and to provide a good harvest, health, fertility, and happiness.

Similar rituals can also be found in Romania, Serbia, Italy and Spain.

The Surva Festival, which first took place in 1966 as a cultural event based on Bulgaria's folklore traditions, is the largest carnival event in Bulgaria and the Balkans.

It is usually held in the last weekend of January, but this year it was postponed with a week, due to the national referendum on nuclear energy that took place last Sunday.