Quesu Casín Competition Activity · Caso, Nalón, Asturias Image of Caso, not of the place itself. Traditionally held at the Arnicio pass on the last weekend in August and moved to Campo de Caso since 2015, it brings together the makers of the designation of origin. It is declared a Festival of Tourist Interest of the Principality of Asturias. Photo: acneuc (CC BY-SA 3.0) What to see and do in Caso