Deep within the Austrian Alps lies the world's largest natural ice cave system

Countries & Cities · Published 30 September 2026 Swipe more like this →

In short: Known locally as the entrance to Hell, the Eisriesenwelt cave stretches over 42 kilometers beneath the Hochkogel mountain. While the vast majority of this limestone labyrinth remains ice-free, the first kilometer is a frozen wonderland preserved by a unique natural ventilation system that keeps the interior temperatures below freezing year-round.

Formed by the erosive power of the Salzach river, the Eisriesenwelt—meaning World of the Ice Giants—is a geological marvel located in the Tennengebirge massif. Its internal ice formations are the result of a delicate seasonal cycle: in winter, cold air currents enter the cave, freezing the meltwater from snow that has seeped through the limestone. During the summer, the process reverses, as cold air flows outward from the depths, acting as a natural refrigerator that prevents the ice from melting.

The cave remained largely ignored by the outside world until 1879, when Salzburg scientist Anton Posselt explored the initial 200 meters. Local residents had long avoided the site, fearing it led to the underworld. Although Posselt published his findings in 1880, they were largely forgotten until speleologist Alexander von Mörk led a series of expeditions starting in 1912. Von Mörk, who died during World War I in 1914, is now memorialized within the cave, where his ashes are kept in a niche inside the cathedral that bears his name.

Today, the site is a major tourist destination, drawing roughly 200,000 visitors annually. Access was transformed in 1955 by the installation of a cable car, which reduced a grueling 90-minute climb to a mere three-minute ascent. Managed by the National Austrian Forest Commission and the Salzburg Association of Cave Exploration, the cave offers a guided one-hour and 15-minute tour. Visitors traverse a one-kilometer path that showcases spectacular formations like the 25-meter-high Great Ice Embankment and the delicate stalactites known as Frigga’s Veil, all while navigating an environment that requires winter clothing even in the height of summer.

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