The hillfort of El Castillo Nature · El Royo, El Valle y La Vega Cintora, Soria Image of El Royo, not of the place itself. On a height of the municipal district are preserved the ruins of an Iron Age castro whose defences reach eighteen metres in width, a sample of the pre-Roman settlement that preceded the present hamlets. Photo: Gartxoak (CC BY-SA 4.0) What to see and do in El Royo