How was it built?!

It is funny, you read about it, and you find out that it seemed to have disappeared until 1620 CE! And, it was written that it was hidden by its own debris! It is further written that it was not excavated until 1931 or so! But, here is a drawing circa "Persepolis by Jean Chardin and al, 1711." You have to look down about 10 lines to find the small version. There is another version also found here that does not expand!

http://translate.google.com/translate?hl=en&sl=pl&u=http://commons.wikimedia.org/wiki/Category:Persepolis&ei=MW_7SpaMM8zlnAemyYyLBQ&sa=X&oi=translate&ct=result&resnum=2&ved=0CAwQ7gEwAQ&prev=/search%3Fq%3DIllustration%2Bof%2BPersepolis%2Bin%2B1827(without%2Bborder)%26hl%3Den%26rlz%3D1T4ADBR_enUS315US315

Which seems to show quite a bit of it obvious to any eye!

Since all of the combustible material had to have burned during Alexander's time, then there should have been almost nothing left but the bricks and stones! It would be very strange if a lot of the material had not been mined for centuries for use elsewhere.
It would certainly be useful if someone on this site could obtain the photographs and drawings of the excavation in the 1930's and after the war!

So, why did it seem not to exist from the times of Alexander until 1620 CE?

Edited by opuslola - 11-Nov-2009 at 18:30