Navia River through Negueira Nature · Negueira de Muñiz, Fonsagrada, Lugo The Navia runs deeply hemmed in through the municipality and here takes in the waters of the rivers Couso and Ibias; its narrow valley, with its steep slopes, marks the natural boundary between Galicia and western Asturias. Photo: Xoán Carlos Fraga (GFDL) What to see and do in Negueira de Muñiz