In the Iberian Peninsula there is a place that is faithful reflection of the Humanity's History. It is known like Raya Seca, the frontier between the spanish county of Salamanca and the portuguese of Beira Alta. In this natural corridor all the civilizations have left their print in paleolithic locations, Celtic castros, medieval towers or fortified cities as Ciudad Rodrigo or Almeida; they have been witness of a fascinating trip that will drive us through the history.