There is one Winkelturm in Stuttgart Feuerbach, that is sometimes open for visitors. Here is a link in German http://www.schutzbauten-stuttgart.de/de-de/f%C3%BC

There is one Winkelturm in Stuttgart Feuerbach, that is sometimes open for visitors. Here is a link in German http://www.schutzbauten-stuttgart.de/de-de/f%C3%BChrungen/%C3%B6ffentlichef%C3%BChrungen.aspx http://www.schutzbauten-stuttgart.de/de-de/f%C3%BChrungen/%C... When these bunker were built in Germany in the 1930's new designs has to be tested to get approval. Does the test site still exists? This would show various designs.