Gobekli Tepe in modern SE Turkey is an impressive megalithic structure – or series of structures. They date back to the early Holocene period – some distance after the so called Younger Dryas Boundary event. After it was deemed past its shelf life the stone circles were buried in soil and and debris to form a hill – a very large mound. The current view of archaeologists is that the megaliths were build by hunter gatherers. This change of opinion is remarkable as previously it was thought hunter gatherers could not have had the manpower to build and plan such monuments, or the organisation skill in order to coerce a large number of people to to work to a set model (let alone the ability to carve symbols in the stones or align the structures to true north). It was thought this was only possible once the Neolithic period had kicked in as farmers were sedantory and had to plan and work out the logistics of growing foodstuffs and all the other kind of jobs farmers do on their properties. Archaeologists also acknowledge that Gobekli Tepe actually overlaps with the adoption of farming in the Fertile Crescent – but what came first, the monuments or the farmers?
The site is less than half excavated and no stone circle has been fully and entirely uncovered. It is a long way down to the first stone circle – and no one knows what date that was erected. In Britain, megalithic structures such as Durrington Walls and Stonehenge appear to have been the product of people with a pastoral economy who moved around the landscape. At a certain time of the year they converged and held ceremonies of some kind, at a specific point in the season. The builders of Gobekli Tepe were not a lot different.
Graham Hancock, and people such as Randall Carson, have latched on to the proximity of Gobekli Tepe to the Younger Dryas event and have suggested, instead, that the builders were the survivors of a major catastrophic event. This is a long running theory of Hancock, a thread that runs through several of his books. The big problem is that he requires just the one major catastrophe whereas not all of the proponents of the Younger Dryas Boundary event theory visualise a single episode affecting people on earth (such as the disappearance of the Clovis fluted flaked stone tool makers) but a whole series of major and minor catastrophes that litter a large part of the Holocene – and the Late Pleistocene (possibly from as long ago as 30 to 40,000 ka, at the point when the Neanderthals disappeared). If Hancock's theory is correct, that a civilisation existed prior to such a catastrophe, archaeologists have yet to stumble on it. Prior to the Younger Dryas there was a couple of thousand years of warm weather (not a lot different from today) but Late Palaeolithic people were at large. Where was this hypothetical civilisation – and what do they mean by civilisation.
There is no inherent reason why a semi nomadic people could not have built Gobekli Tepe as a foci of seasonal worship or celebration – especially if the progenitor of catastrophe was a recurring fact of life, in the sky or under the skin of the earth. HOwever, it is a significant detail brought up by Hancock, the builders used true north in their alignments – or appear to have done so (as the alignments aren't universally accepted). If so the megaliths were constructed with heavenly alignments in mind Hancock would appear to have a point – but does he assume hunter gatherers could not have worked it out for themselves. See www.youtube.com/watch?v=tFlAFo78xoQ