The Cava de Viriato is a fortress built on clay, surrounded by a moat, located in the northern city of Viseu. It is a national monument since 1910.
The camp features an octagonal shape, bounded by strong slopes, with 2000 meters of perimeter and area of 38 hectares; in the spring faces north and west shows traces of a moat. Of the eight remaining slopes and are flyable six.
The Cava was traditionally considered a camp of the Roman era, built by Decimus Brutus Junius (137-136 a.) Or, according to Jorge Alarcão, by military leaders and Cassius Longinus Petreio in mid-century to. C .. More recently, Vasco Mantas, despite considering that within the Cava area there was a Roman camp, attributes its construction to the Arabs.
Only in the sixteenth century that is called the name of Cava de Viriato.