Festival of los Güevos Pintos Activity · Siero, Oviedo, Asturias Image of Siero, not of the place itself. On the Tuesday after Easter Sunday, Pola de Siero fills its streets with hand-painted eggs, sold alongside stalls, dancing and jokes; it has been a declared festival of national tourist interest since 1968. Photo: McBodes (CC BY 3.0) What to see and do in Siero