Devilstone Open Air (aka "Velnio Akmuo" in Lithuanian) is a summer open air rock and metal music festival. It takes place annually since 2009 in the town of Anykščiai, in Lithuania. Devilstone Open Air has included performers playing black metal, death metal, power metal, thrash metal, sludge metal, doom metal, post rock, stoner rock, and progressive rock music genres. Music bands from Europe, North and South America, and Australia have performed in the festival. Devilstone Open Air is usually held in the mid-summer, around the third weekend of July.