We have shared many many greenhouse ideas with you all over time but today we have something totally different. This is called a Walipini or an underground greenhouse.
Grow Test Dot Org has a free pdf plan on how to build an underground greenhouse. I have to say this may be the most unique greenhouse I have ever seen. It would be a really neat way to have a low visibility greenhouse. Why announce that you are growing food to the whole world?
The Underground Greenhouse – Free pdf