http://www.balkantravellers.com/en/read/article/1029
There is no indication that this author actually picked up a piece of flint and tried to scratch a piece of that bedrock. I'm not sure what this reluctance is among archaeologists to do experiments but he simply assumes that everything he has been told about the Mesolithic era is correct and therefore is amazed that these structures could have been built.I am standing amidst evidence that could upset everything we know about our remote past. Imagine such an age that it is still thousands of years to the discovery of metal and that the best cutting tool available is made of a piece of flintstone, with which you will hack 25-ton obelisks out of the bedrock and, carving those frightful animal figures on them, drag them here and erect them.
He does not seem to ask himself the question; "what if we are wrong?"