Eisriesenwelt (Giant Ice World)

Eisriesenwelt are the largest accessible ice caves in the world. The caves are buried in the depths of the Hochkogel mountain range and the labyrinthine tunnels extend for more than 40 kilometers (24 miles). Originally discovered by Anton von Posselt in 1879, the caves only gained prominence after they were 'rediscovered' by Alexander von Mörk in the early 20th Century. It's believed that the limestone cave system has been evolving for millions of years. As the temperature within the cave is always at sub-zero, when snow melts in the spring and drips into the cavern, it cools and freezes in a variety of fascinating sculptures. A stunning example of nature's grandeur, some caves are illuminated in an ethereal blue light that filters in; others are illuminated with lamps that cast strange shadows over the walls, as they bring into focus the weird and wonderful works of natural art .