they had the puma punku site on the documentary called ancient aliens. basically, even people who completely discredit the fact that humans must have had help to build these structures are completely stumped when it comes to puma punku, because the stones there are cut so exact, and so fine that to do that with simple stone tools is virtually impossible even today. on some of those stones, there are lines cut that are 6 milimeters wide and 6 milimeters deep, running down the stones perfectly without any chips or cracks. the stones themselves are made of granite and diorite, so that means the only way to carve them is to use diomond tipped chisels
http://hubpages.com/hub/Ancient-Myst...-in-Tiahuanaco
this is unrelated, but for any lovers of ancient mysteries...
http://members.tripod.com/kon_artz/c...s/stonetec.htm
make sure to go through all the pages^