Construction The erdstall tunnels are very low and narrow – they have a height of and a maximum width of about . Additionally  they feature very tight passages from one tunnel to a lower tunnel called "Schlupf" (slip out) that is too narrow for older or overweight persons – a person needs to crawl under the slip hole, stand up thereby sliding the shoulders through  the skin-tight hole, allowing to crawl onto the higher tunnel. Erdstall tunnels have only one narrow concealed entry point – so there is no second exit tunnel as with an escape tunnel system. Some tunnel systems feature loop tunnels at the end of a tunnel. Most tunnel systems are not longer than . Classification To get a better overview research has come up with a rough classification system  :Herbert Wimmer: Die Regional-Typisierung der Erdställe. In: Der Erdstall. Nr. 26. Roding 2000, S.54-56. Type A has a single long gallery with slip passages and short side slopes . Type B has multiple levels connected at multiple places by vertical slip passages. Auxiliary construction tunnels have been found that were closed after completion. At the end of each tunnel, seating niches have been cut out or the tunnel is widened with a longer seating bench. Type C has multiple horizontal slip passages and there is a round trip tunnel at the end or in the middle that is high enough to walk through upright. Type D has multiple chambers that are connected through tunnels. The slip passages are mostly horizontal in this type.
Construction The erdstall tunnels are very low and narrow – they have a height of and a maximum width of about . Additionally , they feature very tight passages connecting one tunnel to a lower tunnel called a (slip out) , which are typically extremely narrow and impassable for some, as crawling under the slip hole, and then standing up to slide the shoulders through , is necessary to crawl into the higher tunnel. Erdstall tunnels have only one narrow concealed entry point , with no second exit tunnel as with an escape tunnel system. Some tunnel systems feature loop tunnels at the end of a tunnel. Most tunnel systems are no longer than . Classification In his 2000 publication , Herbert Wimmer created a rough classification system for varying types of erdstall :Herbert Wimmer: Die Regional-Typisierung der Erdställe. In: Der Erdstall. Nr. 26. Roding 2000, S.54-56. Type A has a single long gallery with slip passages and short side slopes Type B has multiple levels connected at multiple places by vertical slip passages. Auxiliary construction tunnels have been found that were closed after completion. At the end of each tunnel, seating niches have been cut out or the tunnel is widened with a longer seating bench. Type C has multiple horizontal slip passages and there is a round trip tunnel at the end or in the middle that is high enough to walk through upright. Type D has multiple chambers that are connected through tunnels. The slip passages are mostly horizontal in this type.
A
,
R
from
connecting
R
"Schlupf"
a
R
that is too narrow for older or overweight persons – a person needs to crawl
, which are typically extremely narrow and impassable for some, as crawling
R
stand up thereby sliding
and then standing up to slide
A
, is necessary to crawl into
D
skin-tight hole, allowing to crawl onto the
R
– so there is
, with
R
not
no
R
To get a better overview research has come up with a
In his 2000 publication , Herbert Wimmer created a
A
for varying types of erdstall
D
.