Eisriesenwelt

The interior of the caves.

Eisriesenwelt ("World of the Ice Giants") is a breathtaking natural limestone and ice cave situated in Werfen, Austria, roughly 40 km south of Salzburg. Nestled within the Hochkogel mountain in the Tennengebirge range of the Alps, it holds the title of the world's largest ice cave, stretching over 42 km in length. Each year, around 200,000 visitors explore its stunning icy chambers and formations.

Geology

Layers of zebra limestone under the cave

The Tennengebirge mountains, part of the Austrian Alps, were formed during the late Tertiary period, shaped significantly during the Würm glaciation of the Pleistocene epoch. This range, one of the massifs in the Niedere Tauern, is home to the largest karst plateau in the Salzburger Alps. The Eisriesenwelt lies at the edge of this plateau.

While the cave spans an impressive 42 km, only the first kilometer, open to tourists, features stunning ice formations; the rest consists of limestone passages. The Salzach River carved the cave's intricate pathways through erosion, while its ice formations developed from melting snow that seeped into the cave and froze in winter.

The cave’s unique climate helps preserve its icy wonders. In winter, frigid winds enter the cave and freeze the snow. During summer, cooler winds from inside flow outward, preventing the ice from melting. This natural phenomenon keeps Eisriesenwelt a year-round marvel.

History

The Eisriesenwelt was officially discovered in 1879 by Anton Posselt, a natural scientist from Salzburg, though he explored only the first 200 meters. Before his discovery, locals avoided the cave, believing it to be an entrance to Hell. Posselt documented his findings in a mountaineering magazine in 1880, but his report was largely overlooked.

Years later, Alexander von Mörk, a Salzburg speleologist, revisited Posselt's discovery. Starting in 1912, he led multiple expeditions into the cave, sparking further exploration. Von Mörk, who tragically died during World War I in 1914, was honored with an urn containing his ashes placed in a niche within the cave.

In 1920, the first explorer cabin, Forscherhütte, was built, along with initial routes up the mountain, paving the way for tourism. The construction of a second cabin, the Dr. Oedl House, followed, alongside paths from Werfen and Tenneck.

The ascent was revolutionized in 1955 with the installation of a cable car, reducing the 90-minute climb to just 3 minutes. Today, Eisriesenwelt is managed by the Salzburg Association of Cave Exploration under a lease from the National Austrian Forest Commission, which retains a portion of the entrance fees.

Visiting

Entrance of the cave

The Eisriesenwelt cave is open to visitors from May 1 to October 26 annually. During July and August, operating hours are 9:00 a.m. to 4:30 p.m., while in May, June, September, and October, the hours are 9:00 a.m. to 3:30 p.m. Temperatures inside the cave remain below freezing, so warm clothing is highly recommended. Photography is prohibited once inside the cave.

The guided tour begins at the cave entrance and progresses to Posselt Hall, a large chamber featuring a stalagmite called Posselt Tower at its center. Nearby, an ashen cross marks the farthest point reached by Anton Posselt during his initial exploration. From there, visitors encounter the Great Ice Embankment, a towering formation of ice reaching 25 meters high, showcasing the cave's most extensive ice growth.

Next is Hymir’s Castle, named after a giant in Norse mythology, where ice formations include Frigga’s Veil (also known as the Ice Organ), formed by delicate stalactites.

The tour proceeds to the Alexander von Mörk Cathedral, one of the cave's largest chambers and the resting place of von Mörk's ashes. The final stop is the Ice Palace, located 1 kilometer into the cave and 400 meters underground, offering a breathtaking conclusion. Visitors then retrace their steps to the entrance, completing the round trip in approximately 1 hour and 15 minutes.

Gallery

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  A closeup of one of the ice formations.
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  Ice formations.
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  Looking down from the cave onto the trail, which is the only way of access to the cave.
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  View of the landscape from the cave.
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  Access to the cave.