Hillfort of a Ribeira Nature · A Gudiña, Viana, Ourense Image of A Gudiña, not of the place itself. A pre-Roman fortified settlement set above the valley of the River Ribeira; its position commands one of the natural passes between the Galician uplands and the Zamoran comarca of Sanabria. Photo: Mario Sánchez (CC BY-SA 2.0) What to see and do in A Gudiña