Ключевые слова: 7, cercedilla, ecosystem, environment, forest, green, hiking, hill, house, landscape, madrid, mountain, national, national park, natural, natural park, nature, observatory, park, peak, peaks, pine, refuge, relax, relaxation, reservoir, rock, route, scenery, sierra de guadarrama, sky, spain, town, travel, tree, view, viewpoint, village, wood,