The fascination of Hölloch – second longest cave system in Europe

Lake Lucerne Region

The Hölloch is an impressive karst cave system located in Muotathal in the canton of Schwyz. With a known length of over 209 km, it is the second-longest cave system in Europe and the eleventh-longest in the world. With a depth of 1033 m and a length of 207 km, it is the largest cave system in the world. The entrance to the Hölloch lies above the hamlet of Stalden in Muotathal.

Hölloch stalactites and stalagmites / Photo Brigitte Heller

Hölloch stalactites and stalagmites / Photo Brigitte Heller

The Hölloch in Muotathal sets a new world record with its gigantic dimensions: no other cave system in the world combines such a great depth with such an impressive length. With a height difference of 1033 m between the deepest and highest point of the cave and an explored length of 207 km, the Hölloch is a unique natural wonder.

Good to know:
The temperature is a constant 6 degrees Celsius in both summer and winter; the humidity is almost 100%.

The Höllloch in Muotathal is one of the largest cave systems in the world and stretches over an impressive length of 207 kilometers. Over a period of almost a million years, the water has unleashed enormous forces underground and shaped the cave into its current form.

With its vast expanse and geological significance, the Hölloch attracts cave explorers and nature lovers alike. The discovery and exploration of this fascinating cave system is a remarkable scientific achievement that gives us a rare insight into the mysterious world beneath the earth’s surface.

Hölloch with world record

The Muotathal cave sets a new world record: It is the largest cave system in the world both in terms of its depth, with a height difference of 1033 meters between the deepest and highest points of the cave, and in terms of its explored length of 207 kilometers.

Structure of the Hölloch cave system

The cave system in Muotathal consists of three levels, the lowest of which is mainly below the karst water level and is therefore largely filled with water. Due to the geological rock strata, the passages generally slope downwards to the north and only a few run horizontally.

Several cave explorers have already been surprised several times by water ingress and had to remain in the cave for several days. Since 1980, four additional entrances have been discovered or opened up, meaning that trapped people can now be reached via an upper entrance, for example. However, access is extremely challenging and not suitable as a rescue route. There are also food supplies in various bivouacs that allow several people to sustain themselves for a few days. These include the so-called Dom bivouac for tourist tours and several research bivouacs for speleologists. In addition, the water situation in the Höllloch has been better researched, and care is taken to minimize risks, especially for tourist tours.

Anyone who discovers a previously unknown passage or room in the cave has the right to name it. Names are often chosen to reflect the special characteristics or peculiarities of this place, such as the “snake passage” or the “knight’s hall”. In the early years of exploration, passages were also named after the discoverer.

Guided tours Hölloch Muotathal

Various guided tours and events are offered at Hölloch Muotathal:

  • 2-hour short tour
  • Short expedition “Hölloch-Parcours”: 3.5 hours
  • Fascinating day expedition 7-11 hours
  • Multi-day expedition with overnight stay in a cave bivouac
  • Company and club programs (sporty or leisurely)
  • Atmospheric cave raclette by candlelight and cave music
Hölloch guided tours / Photo Brigitte Heller

Hölloch guided tours / Photo Brigitte Heller

Explore the adventurous underworld on a captivating guided tour and explore the fascinating caves of the Muotathal valley together with a local guide. You will be impressed by the breathtaking sights of stalagmites, stalactites, deep gorges, magical rock formations, glacial mills, fossils and lakes. An unforgettable experience for adventurers and explorers.

The Höllloch complex offers various expeditions to choose from, ranging from short 1.5-hour tours to multi-day adventures with overnight stays in a bivouac. Whichever option you choose, you will embark on a unique journey into the fascinating underworld.

Please note that the guided tours in Hölloch Muotathal are similar to a mountain tour in rough terrain. However, exposed sections are well secured. Good footwear, warm clothing and sure-footedness are required for the short tours. For the longer expeditions, climbing ability is also required. If required, you can hire the necessary special equipment on site to make your expedition safe and comfortable.

Shortly after Schwyz, turn off towards Muotatal and you will feel that you are getting closer to the Hölloch. It becomes noticeably shadier and cooler, the air fresher. The entrance to the caves is located above the hamlet of Stalden.

More information at: Hölloch guided tours

Video Hölloch – the second largest natural cave in Europe

The “Hölloch” in Muotathal is the largest natural cave in Switzerland and the second largest in Europe.

Hölloch - zweitgrößte Naturhöhle in Europa

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Video Höllloch Cave in Muotathal, Switzerland

Hölloch Cave in Muotathal, Switzerland

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Video The longest caves in western Europe

Located in canton Schwyz in central Switzerland, the Hölloch caves are the longest – at nearly 200km – in western Europe. “Hölloch” translates into English as Hell’s Hole, but the first syllable of the word means “slippery” in the local German dialect.

The longest caves in western Europe

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