Ключевые слова: aerial, aerial view, autumn, birds, bulgaria, countryside, dam, drone, ecology, engineering, environment, fall, forest, green, hydro, hydroelectricity, izvor, izvor reservoir, konyavska, konyavska mountain, land, landmark, landscape, mountain, national park, natural, nature, outdoors, pass, pernik region, pollution, power, radomir, reservoir, resource, river, rural, scenic, sightseeing, tourism, travel, tree, view, water, wilderness, wildness,