Ключевые слова: adventure, ancient, beam, beautiful, cave, cavern, color, dark, darkness, deep, depth, earth, entrance, exit, exploration, faith, geologic, geology, grotto, ground, hole, inside, landscape, light, limestone, mountain, mysterious, mystery, natural, nature, nobody, old, optimism, ray, rock, shadow, speleology, stalactite, stalagmite, stone, subterranean, sun, sunlight, sunshine, tourism, travel, treasure, tunnel, underground, wall,