In ancient Bulgaria, wearing masks was believed to provide protection from evil, ensure a successful harvest, and guarantee health and fertility for humans and farm animals

Many of these pagan rituals, which were later incorporated into Christianity, are still performed in eastern Bulgaria between the holidays of Christmas and Easter. Rituals held around the New Year are known as Surva, while those performed around Easter are known as Kukeri. Today the International Festival of the Masquerade Games, held in the town of Pernik, still celebrates these customs. During the festival, which is the biggest event on the Balkan Peninsula, single men and women called Kukeri and Survakari, don traditional Bulgarian costumes and elaborate masks and parade down the streets of Pernik.

Many legends date back to the 7th centuries the First Bulgarian Empire, however other tales relate to the Thracian times. In 1995 the International Federation of Carnival Cities accepted the town of Pernik as a full member. In June, 2009, Pernik was proclaimed as the European capital of Survas & Mummers and included in the UNESCO list of the Intangible Heritage of Humanity.

The event is known as one of the greatest carnivals of the Balkan. The main idea of the carnival, which started on 1966, is reviving and renewal of ancient culture traditions with emphasis on traditional Bulgarian dress. 

The carnival reaches its climax in a giant disguise/ mask parade with the participation of representatives from Bulgarian villages and lot of groups from out of the country.

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