Trail of la Calzada Romana de Rioseco Activity · Sobrescobio, Nalón, Asturias Image of Sobrescobio, not of the place itself. A circular path of about eleven kilometres that starts at Rioseco and follows the paved course known as the Roman road; it is one of the waymarked itineraries of the Redes natural park, catalogued as PR-AS 122. Photo: Grandawiki (CC BY-SA 4.0) What to see and do in Sobrescobio