azud del acueducto hiking route, sierra de guadarrama national park, spain

azud sierra guadarrama rio frio acueducto path walk trekk trekking route walking tour hiking mountain valley river riverbed landscape scenery nature wildlife environment ecosystem biosphere tourism ecotourism tranquil scene view natural park conservation area national wildland recreation environmental water freshwater flowing forest pine scots tree pinaceae coniferous trunk woodland segovia castile and leon spain