Castro dos TrEs Rios is located in Parada de Gonta (Tondela, Viseu), in Beira Alta Region, Center of Portugal.-The project aims to carry out a detailed study of the archaeological site, with a view to clarifying fundamental questions, such as the definition of its chronological features, and the way in which its occupation evolved in historical transition moments.-With regard to the archaeological site configuration, the project aims to identify the limits of the ancient settlement, as well as housing structures, with a view to reconstituting its architectural plan as complete as possible, as well as the definition of sectors of greater archaeological potential, for purposes of safeguarding heritage.