Ключевые слова: abstract, amazing, ancient, background, beautiful, black, bright, cave, cavern, caving, dark, darkness, deep, earth, entrance, environment, exploration, formation, geologic, geological, geology, grotto, ground, hole, inside, landscape, light, limestone, mineral, mountain, mysterious, mystery, natural, nature, old, opening, ray, rock, shadow, speleology, stalactite, stalagmite, stone, texture, tourism, travel, tunnel, underground, wall, wild,