During the Roman occupation of this territory the populations already inhabited preferentially in the slopes and in the valleys of the main waterways, with natural highlight for those of Ovil and Douro.
This strategy of occupation continues for the medieval period, standing out the hill of the Castle of Matos. Strong brand in the landscape and the identity of Baião because it was the place chosen by the lord for the construction of the castle that in the middle of the century. XI commanded the destinies of the Bayam. It was a fortification in wood, destroyed by fire, in the ashes from which the spurs of a knight were found, unique exemplar of the period of the Christian reconquest known until then in the whole national territory.
This site was also occupied during recent prehistory, by Bronze Age populations. Under the medieval vestiges are vestiges of a hut floor and other archaeological materials highlighting the ceramic mold of the foundry of a sword, guarded by the archeology nucleus of the municipal museum of Baião.
