Many times people ask me how high can you build with earth. Well, for instance, one can take a look at the 1000 year old earth-built skyscrapers in Yemen http://www.earthbagbuild.com/brief_history.htm. Now, I have not been in Yemen yet, but last year, my friend Shea and I went on a trip in search for the tallest earth building in Germany: the Rath House. It was built around the year 1850 with rammed earth (compressed soil into a formwork), the house is 6 floors height and it is a combination of loadbearing earthen walls and timber structure.
By the way, if you see a tiny man in the left corner of the picture, that, my friends … is Shea Hagy.