Der Spiegel probes the long-buried secrets of the Erdstalls – Bavaria’s ancient underground mazes:
At least 700 of these chambers have been found in Bavaria alone, along with about 500 in Austria. In the local vernacular, they have fanciful names such as “Schrazelloch” (“goblin hole”) or “Alraunenhöhle” (“mandrake cave”). They were supposedly built by elves, and legend has it that gnomes lived inside. According to some sagas, they were parts of long escape tunnels from castles.
In reality, the tunnels are often only 20 to 50 meters long. The larger passageways are big enough so that people can walk through them in a hunched position, but some tunnels are so small that explorers have to get down on all fours. The tiniest passageways, known as “Schlupfe” (“slips”), are barely 40 centimeters (16 inches) in diameter.
The ground beneath the southern German state of Bavaria is literally perforated with these underground mazes — and no one knows why.
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A few radiocarbon dating analyses have also been performed, and they indicate that the galleries date back to the 10th to the 13th century. Bits of charcoal recovered from the Erdstall tunnels in Höcherlmühle date back to the period between 950 and 1050 A.D.
Heinrich Kusch, a prehistorian from the Austrian city of Graz, believes that these results are incorrect. He suspects that some of the subterranean systems were built about 5,000 years ago, in the Neolithic period. For several years now, he has been probing Austria’s Steiermark region with giant drills for “gateways to the underworld.”
But Kusch’s theory has lost some of its appeal. All of the radiocarbon dating analyses completed to date indicate that the tunnels were built in the Middle Ages, challenging the validity of the prevailing school of thought. It holds that the tunnels were built during the Migration Period (known as the “Völkerwanderung” in German) in the 5th and 6th centuries, when entire tribes left their homes and abandoned the cemeteries of their ancestors. The assumption was that the tunnels and galleries were created so that the dead could still be venerated.
It is clear, at any rate, that they were built by professionals. They dug the tunnels in a kneeling position, using wedge-shaped tools held with both hands. Every few meters, they chiseled cavities into the walls for their oil lamps. They dug the longer passageways in serpentine form to reduce the pressure from the surrounding earth. Supporting planks were not used.