Ключевые слова: adventure, ancient, architecture, background, cave, cavern, dark, deep, entrance, environment, europe, exploration, foliage, forest, gate, geology, green, grotto, hole, inside, landmark, landscape, light, moss, mountain, mysterious, nature, old, outdoor, park, rock, scenery, scenic, silhouette, sintra, speleology, stalactite, stone, sun, time, tourism, travel, tree, trunk, tunnel, underground, view, wild, wood,