Ключевые слова: a pic, abseil, abseiling, abyss, adventure, black, cave, caver, caving, challenge, climbing, copy, dangerous, dark, descend, down, dungeon, exploration, exploring, extreme, geology, haunting, hole, light, limestone, mine, mountain, ore, pit, pothole, potholing, rappel, rappelling, remote, rock, rope, safety, secure, shadow, silhouette, sinkhole, space, speleology, spelunker, spelunking, sport, stone, suspend, underground, vertical,