A Thread from @carmindabrendel: "THE TUNNEL SYSTEMS From a very long time ago they built networks of tunnels beneath the ground [...]"
THE TUNNEL SYSTEMS From a very long time ago they built networks of tunnels beneath the ground Especially mountainous regions ???? https://www.atlasobscura.com/articles/exploring-the-secret-nazi-tunnels-under-a-german-vacation-town… https://t.co/ZM3C
![A Thread from @carmindabrendel: "THE TUNNEL SYSTEMS From a very long time ago they built networks of tunnels beneath the ground [...]"](https://wego.social/upload/photos/2021/02/hQkZT7Ucd9SJGRc4zRbX_url_image.jpg)
