Onís is a municipality and a parish in the Autonomous Community of the Principality of Asturias, Spain. The municipality is bordered on the north by Llanes, on the south by the province of León, to the east by Cabrales and to the west by Cangas de Onís. The area of the municipality is 75 km2, being more of a third of its territory in the Picos de Europa National Park. The population is dispersed over various population centers, being its capital de Benia de Onís. In 2007, the population is of 920 inhabitants, increasing remarkably during holiday times.