For what reason the underground passages and chambers have been built, is a mystery to this very day. As a rule, the Erdställe do not contain any evidence of regular use by humans or by animals. It appears as if many of them had been abandoned soon after completion and never were frequented again.
Many Erdställe are situated beneath farmsteads that have their origins in the Middle Ages. Frequently, they are found in the vicinity of old churches or in a special context with fortifications, and often even in open ground without any connection to a building.
There are many different ideas about the purpose the Erdställe might have served. Were they mundane structures, for example hiding places for precious goods or temporal refuges in times of unrest? Or were they cult places, soul chambers, or gathering places of medieval Christian sects?
Only one thing is clear: The Erdställe were not intended as shelter or stable for cattle (cf. German ‘Stall’, plural ‘Ställe’). The Old and Middle High German word ‘stal’ means ‘living place’, ‘location’, or ‘site’ (cf. English ‘stead’). The term ‘Erdstall’ first occurs in the urbarium of Asparn an der Zaya (Lower Austria) under the year 1449, significantly later than the time when the tunnels were constructed. Probably, ‘Erdstall’ also is not the High Medieval name for the structures, but only indicates that on the eve of the modern era, people already did not know anymore what the Erdställe originally were about.
There are valid arguments in favour of several possible forms of use – as well as counterarguments. Turn the panels, and see for yourself!
‘…and declare many of them, not all, as serving a cult … But what these means and purposes consisted in, we do not know, and we must, apart from the uncertainty of mere presumptions and deductions, be content altogether, that there lie secrets over these dark corridors and chambers which we sufficiently to solve are the less able as so much of what those ancient peoples practiced in custom and religion is a mystery for us …’
Frequently – up until the 19th century – it has been reported that people escaped into Erdställe for shelter in times of war. Many Erdställe are situated near to or beneath buildings.
… it is unclear whether the Erdställe were in fact intended as places of refuge when they were built. There is no exit but through the entrance, and the ventilation often is inadequate. Once discovered, it was easy for enemies to smoke out the hideout. This interpretation also does not explain the artificial bottlenecks (slips) of the Erdställe.
Cool and dark: Just as in earth cellars, the climatic conditions in Erdställe are well suited for the storage of food.
… for a long-term storage of food, the passages of the Erdställe generally are too narrow, too low, and too impractical. The slips remain a mystery in this interpretation, too. Also, many recently discovered Erdställe do not show any signs of wear, such as haul marks on the ground made by the dragging of crates or sacks. Instead, it even seems as if after their completion, they never were set foot in again.
Many Erdställe are in fact expertly constructed using mining techniques and tools. They are not connecting tunnels between a point A and a point B, but always terminate underground. Commonly, there are no indications to betray any prolonged usage, and tool marks are still fresh. After all, Erdställe often are found in areas in which mining was conducted.
… Erdställe do not run directly downwards, as if prospecting, but remain rather close to the surface. The passages of medieval mines may have a similar cross-section, but the general layout of the corridors obviously follows different principles. This interpretation fails to explain the presence of the slips and the chambers of the Erdställe, as they are entirely unnecessary for the working of veins of ore.
It seems that Erdställe frequently were built in places (re)settled only in the High Middle Ages. The new settlers had to leave behind the graves of their deceased ancestors in their old homelands. Did they build the Erdställe at their new settlement sites in order to offer them to the souls of their ancestors as dwelling places? This idea may be supported by the fact that Erdställe apparently were not entered regularly and often look unused.
… why would it have been necessary to build such elaborate and complex underground structures with slips for the use of Christian souls, which were thought of as being purely spiritual, after all? Or does this indicate the survival of pagan concepts and customs?
This is based on the notion that both physical and emotional afflictions can be ‘wiped off’ by squeezing through a narrow passage: The ailment is ‘snagged’, as it were, on the earth of the bottleneck walls, and the sufferer emerges cleansed.
… in all places where this custom is known to have been observed, it is not necessary to pass through the bottleneck a second time on the way back to the exit – on the contrary, this would possibly mean that the cleansing was undone. Besides, clear evidence of abrasion would have to be expected in the Erdställe and their slip holes, but there is none.