Surva is a festival taking place in Pernik, Bulgaria. Every year, the last weekend of January, tradition gathers people from allnover the country, region, and world to participate in casting out the evil spirits from the land. Kukeri are people dressed in hand-made masks and garments, depicting beasts, animals, and demons. They dance under the accompaniment of Bulgarian folklore music and their heavy brass bells. The sound of the bells is said to cast terror into the unclean spirits of the evil entities, keeping them away from people and property. 
The ritual is observed across Bulgaria and in many neighbouring nations, and predates Christianity.
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