Arcos de Valdevez (Portuguese pronunciation: [ˈaɾkuʒ ðɨ ˌvaldɨˈveʃ] ⓘ) is a municipality along the northern frontier of Portugal and Galicia (Spain).
The first settlements in the area of Arcos de Valdevez occurred between the fifth and third millennium B.C., verified by archaeological investigations from many of the funerary mounds within the municipality, such as Núcleo Megalítico do Mezio.
This period of prehistory and the Roman occupation known not just for its influence on toponymy, were important for many of the defensive and habitation structures that dot the landscape of the municipality.
In documents dating back to the tenth and eleventh centuries, there were several military, social centres, and infrastructures that had been built along these northern positions.
Arcos de Valdevez is situated in the northwest Portuguese peninsula of the historical province of Minho, in the district of Viana do Castelo.
The municipal seat of Arcos de Valdevez, the city specifically, is composed of the civil parishes of Salvador and São Paio, which together account for a population of approximately 2204 inhabitants.
The urban agglomerations of Arcos de Valdevez coincide roughly with the principal roadway, the Estrada Nacional E.N.101, that links Braga with Monção.