Ключевые слова: arch, attraction, background, beauty, blue, bulgaria, canyon, cave, cliff, country, destination, environment, europe, famous, forest, formation, geology, gorge, green, hiking, hill, landmark, landscape, monument, mountain, national, nature, old, outdoors, panorama, park, peak, rock, rocky, sandstone, scenery, scenic, sky, stone, summer, texture, tourism, travel, trees, valley, view, water, wilderness, wood,