Orda Cave RUSSIA
There is no daylight zone in the Orda Cave, and the temperature is only 42 degrees Fahrenheit year-round. But the result is mystical: giant white grottoes and labyrinths of narrow passages decorate this otherworldly site. The length of its flooded portion reaches almost 17,000 feet, and the cave is shallow, with a typical average depth at about 26 feet, so you can stay and explore with extended bottom times. The inner space of the cave is decorated with sculptures of fragile gypsum. The most famous of them are White Dragon and the silhouette of a woman on the wall, the Lady of Orda Cave.