Demons’ Dungeons or Soul Storage?

Ley tunnels are treated as one of the favorite myths in Anglo-Saxon Europe. After the discovery of the 700th such tunnel in Bavaria alone, archaeologists decided to make a major stab at unraveling their secrets. As usual, archaeologists' answers just produced many more questions. 
The latest such tunnel was found near the Bavarian capital Munich by an investigating cow. She wasn't so much looking for subterranean passages as for the freshest grass, but all the same. The tunnel she discovered was about 25 m (82 ft) long and like all of its kind very narrow. Folklore names dwarfs and the little people as builders of these tunnels and they reputedly still live there. 

While other finds had been completely disregarded by archaeologists, historians, or any other specialists, this time they descend in force on the latest find. Geologists, local historians, hobby ley tunnel experts, archaeologists, and engineers teamed up to get the perpetual mystery demystified. What they are up against, though, is daunting. 

All these tunnels share common characteristics. They are empty like a merchant's soul, as if someone had swept them out before closing them up. So far, nothing has been found inside them, no pots, no coins, no shards, no bones, and no artifacts of any kind; one tunnel contained an iron plowshare, another three heavy millstones. And that's it in thousands of tunnels found so far. The absence of any objects makes it virtually impossible to reliably date their construction as archaeologists want to do. Only the rubble used to close them has so far been securely dated: All of them seem to have been closed up at the beginning of the 13th century AD. That they seem to have been closed up at the same time would imply that they had an open end up to that time. Some few tunnels contained a bit of wood or a bit of charcoal; carbon dating of these remains point to a construction time in the 10th century or later. 

The tunnels found so far have been linked to medieval buildings that are either still existing or can at least be deduced to have stood there and then lead out into nowhere. Some seem to have been built out in nowhere land with no building attached or even near. The tunnels are quite long, very narrow and not very high. They have spaces where they are no more than 40 cm (16 inch) in diameter. And finally, they have never been mentioned in writing prior to the 13th century. As far as written history is concerned, they don’t exist. That means either they were built and kept a secret, or they were so common that everybody knew about them and didn't need to be told what they were for. 

Geographically, ley tunnels have been found on the British Isles and on the European Continent from the Iberian Peninsula through France and Germany into Hungary. All in all there are several thousand of them, and nobody so far has bothered to find out why they were built and what they were used for. Where facts are scarce folklore and theories flourish. 

The Folklore

Once the tunnels had been sealed up and forgotten, folklore took over to explain these tunnels whenever they were found due to collapse or when someone dug into one. Norwegians and Swedes simply called them lønngangen (secret passages), in German they became Erdställe, Schrazellöcher, Erdweiblschlupfe, or Alraunenhöhlen (hiding places for dwarfs, the little people, or goblins). As many of these structures ended on or near buildings, the famous Gothic literary device of secret passages out of manor houses and castles was born. And in the 20th century, ley lines and ley tunnels were added to the profuse mythical use of these tunnels. Even Harry Potter couldn't do without one. 

The Druid Tunnel Theory

The building technique for the tunnels is low tech; there are no supporting beams or any other kind of support or roofing. They could have been built as far back as the Neolithic Period. That has inveigled some people to attribute the building and use of these tunnels to the druids. Their only proof for this is the absence of any positive dating material. And the latter will apply to all the following theories as well, I’m afraid. As for positive proof: The Druid theory is a non flyer.

But even if the construction was low technology, the diggers were still professional about it all. Every few meters there are niches dug into the walls to take lamps; and to lessen the pressure from the ground above the tunnels were dug in a zigzag pattern. 

The Treasure Trove Theory

The weakening of the Roman Empire was a time when many people started to move across the continent. During the 5th century, Vandals, Visigoths, Ostrogoths, Bavarians, Burgundians, Franks, Allemans, Thuringians, Lombards, and many others were uprooted from their traditional homelands and ended up in Africa, the other end of Europe, or just a few valleys from where they set out from in the first place. Before they left, they dug these tunnels to hide the valuables they couldn't take with them. 

What the proponents have so far failed to explain is the fact that in all these tunnels nothing has been found, not a lost penny, not a shard of a broken pot. Probably the owners once settled in their new place flew back economy to pick up their stuff and swept it clean before handing over to the new owners? 

The Safe Refuge Theory

When the Vandals and their friends started moving all over Europe, times were obviously very insecure. People that wanted to stay put built these tunnels as a safe refuge to hide in when trouble appeared on the horizon. They would hide there while their homes were pillaged and would have crept out again after the danger had passed. There are those that maintain the theory, too, for the time between the 10th and 13th century when the East of Europe was devastated by Magyar plunderers. While this might sound plausible in regions bordering the Magyar sphere of influence, it doesn't make a lot of sense for Spain or the central region of France. 

And imagine the people retreating into their hiding place. To stay there for more than an hour, they probably had to go into suspended animation. The tunnels are so tight they don’t let in a lot of air; people who go in to explore the tunnels usually get dizzy after a few meters for lack of oxygen. The refugees would have had to creep in one after another and then crouched in that confined space possibly for days on end. They obviously cleaned out their refuge after use assiduously as no human refuse was ever found in any of them, not a single little bone from their food, not a scrap of fabric from their clothes. They must have been extremely tidy housekeepers. And as an afterthought, most of the tunnels or parts of them are too narrow for pregnant women; they seem to have been expendable. 

The Ancestor Worship Theory

Again, when the Vandals and their friends ended up at their destination or wherever they decided their destination was, they had a problem. They had crossed Europe and left the burials of their ancestors behind. As cheap flights were not available to go and venerate their ancestors, they built empty burial chambers to be able to communicate with them all the same. 

Part of this ancestor worship was the sharing of food, and no tunnel has contained anything that would indicate any food ever having been there. The Vandals ended up in North Africa, the Burgundians and Allemans ended up in Switzerland, the East of France, and the Black Forest, and no tunnels have been found in either location. 

The Store Room Theory

The tunnels were narrow and long, just about the most impractical thing you could wish for to put your stores in. Do you need the apples? They were stored first, so please get everything else out first. This doesn't sound like our forbears who usually were immensely practical. And as to live stock, there isn't a single tunnel so far that has even a whiff of animal dung in it. I don’t think anyone was ever that tidy. 

The Penitents' Cell Theory

Tunnels were found near monasteries and churches as well; and this gave rise to the idea that they could have been used as penitential cells for sinners. Considering the lack of oxygen, that would have been a rather permanent arrangement. And again, no food left-over or human feces have ever been found in a tunnel. The idea has also been extended to the use for criminals. But if I remember my history lessons correctly, neither the very holy nor the very unholy were ever known for fastidious cleanliness.

The Healing Temple Theory

Adding the Druids and some healing practices used in Greece and Rome led to the idea that the tunnels could have been used as places of healing where people stripped off their illnesses or sent their dreams into the dark. The only bit that might support this theory would be the zigzag pattern used to build the tunnels; sort of like a snake. The lack of air inside the tunnels might have led to a rather permanent solution for sick people, though. 

The Soul Storage Theory

You didn't misread that. There is a theory that claims that these tunnels were used to store souls. Souls of dead people, obviously, as the living usually object to being parted from them. The theory is based on the fact that the geographical distribution coincides to some extent with the erratic wandering and preaching of Irish saints converting continental pagans to Christianity. The storage of souls to await the final judgement was after all a problem, and keeping them near to be resurrected with their loved ones might seem like a good idea.

At the beginning of the 13th century, though, the Catholic Church invented Purgatory and promoted this travel destination extensively together with Heaven and Hell. As all souls now had a destination even if they weren't going straight to Heaven or Hell, the current lodgers of the tunnels were asked to move and the entrances were blocked up. 

This might even work out, if the geographical distribution would actually coincide with the wandering of said Irishmen. Beliefs in the afterlife of pagan Celts would have been near enough to warrant such beliefs being transported into Christian custom like so many others. There is a catch, though. Saint Columba and Saint Gallus traveled and preached extensively in Switzerland, the East of France, and the Black Forest. Gallus even ended up near Lake Constance where the monastery and city of St. Gall were founded. And there are no such tunnels to be found in that area. 

The Demons’ Dungeons Theory

And finally my favorite theory: the demons' dungeon. The tunnels were used to imprison demons, hobgoblins, bad ghosts, the undead, and other creepy crawlies of the supernatural. Some few tunnels show methods to block them off, but only a few. There is one find of a relief showing a hobgoblin. Otherwise the tunnels seem to have been open at the entrance. I personally would have found it unsettling to know that the opening to a place where demons rage led directly into my cellar. 

However you turn it, the lack of evidence makes almost every explanation possible. Feel free to start your own theory. One thing you may be sure of: You’ll find all kinds of spiritual and religious weirdos propagating their own brand of 'explanations'.

Further reading
Doors to the Otherworld
Cologne Cathedral: The Shrine of the Magi
The Devil's Christmas Song