Ключевые слова: background, big kalin, bulgaria, clouds, dam, environment, europe, forest, green, hiking, hill, kalin, kalin dam, kalin reservoir, karagyol, kyustendil region, landmark, landscape, meadow, mountain, mountaineering, national park, nature, outdoor, panorama, park, pastra, peak, recreation, reservoir, rila, rila mountain, rila national park, rock, rocks, route, scenery, small kalin, snow, summer, tourism, trail, travel, water,