Hillfort of o Covelo Nature · Viana do Bolo, Viana, Ourense Image of Viana do Bolo, not of the place itself. A castro enclosure known as O Castelo, in the parish of Covelo, one of the seven fortified settlements catalogued in the municipality along with those of Punxeiro, Grixoa, Pontón and Quintela de Edroso. Photo: Estevoaei (CC BY-SA 4.0) What to see and do in Viana do Bolo