The National Park of Monfragüe has one of the best preserved traces of Mediterranean forest in Spain . It lies in the province of Cáceres , in the centre of a triangle formed by Navalmoral de la Mata , Plasencia and Trujillo . Declared a Natural Park in 1979, Monfragüe occupies an area of 17,852 hectares . The River Tajo and its tributary the Tiétar, provide the waterway, over which stand great rocky cliffs on which breed spectacular colonies of Griffon Vultures, as well as other birds of prey.