Mining know-how: How were the Erdställe constructed?

The Erdställe were dug into the rocky ground using traditional methods of mining as well as great expertise in engineering.

The structures are sound even without brickwork lining or ground supports and go down only as far as 8 metres, thus remaining quite close to the surface. Tool marks can occasionally still be discerned clearly on the walls. They permit conclusions regarding the type of the tools used in the building of the Erdställe.

Tool marks in the Erdstall of Grasfilzing, Arnschwang parish, Lkr. Cham, Germany. (Photo: Birgit Symader)

Digging a corridor of an Erdstall was hard and exhausting work. Here, two forms of tunnelling are depicted: to the left, using a chisel and mallet; to the right, work with a pick (or pickaxe). (Drawings: Martin Straßburger)

The tasks of modern Erdstall research

Of greatest importance, when a new Erdstall is discovered, is the documentation of its undisturbed ‘as-is condition’. This is the only way to ensure that the Erdstall can be awarded protection status as a listed ground monument. For this, researchers survey and measure the tunnel system (either graphically or digitally), describe features such as niches, chambers, and slips, and draw a plan. In optimal conditions, they take samples from undisturbed areas for scientific analyses. The Bayerisches Landesamt für Denkmalpflege pools and coordinates all information. Ideally, the new data and results get published.

Another task of the researchers is to assist owners of Erdställe. The Arbeitskreis für Erdstallforschung e. V. (‘Working Group for Erdstall Research’) helps with the preparation of security concepts and serves as mediator between the owners and the authorities, for example.

Impressions

A small niche, a section of wall with tool marks, and a section of wall and floor from the Erdstall in Rabmühle.

Impressions: Birgit Symader