During the archaeological campaign in “Campo della Fiera” (Orvieto - Umbria) it was discover an important archaeological situ, that whose frequentation turns is many extended since Etruschi (VI sec. a.C.- XIV sec. d.C.). The paleogeographic evolution map of this area based on the geologic, geomorfologic and fotogeologic study of the place confirm this archaeological hypothesis . The paleogeographic evolution of the area among “mesa” of Orvieto and Alfina plateau, appears correct with aspects of the place about the historical-archaeological development and about the natural mechanisms that was the cause of actual configuration of the place. It was also obtained a geo-archaeological GIS, with data base geological/geomorphological and archaeological data too.