What do you think of this?
http://en.wikipedia.org/wiki/Göbekli_Tepe
I find it amazing that such buildings existed before agriculture was
established. In schools we learned that civilization started somewhere in
Mesopotamia around the third millennium BC, perhaps in Harrapa and
Indus valley some centuries before. Now we have to rethink prehistory
again and place the beginnings at the 9th millennium BC. What I find
more important is that hunter societies could also have great
civilizations. It looks we should also to rethink the starting ages of
agriculture.