The pyramids, and other similarly aged buildings around the world, do not support the perceived timeline of man and his abilities. It was simply not possible to build those structures with the technologies credited to the time period of their construction.

In fact, many engineers claim we still aren't able to recreate them as they are, even with all of our advanced technology. They are simply too massive and would require tools that don't exist yet. Even if it were physically possible, the effort would drain our labor pool and the resources needed to support that pool.

Societies that take on such large projects, even with slave labor, must provide for that labor force with at least minimum life sustaining resources. This suggests not only and advanced technology, but a level of affluence that historians don't credit to the people in their linear view of society and its evolution.

Given that evidence for such affluence and technology is not present, the only conclusion that can be drawn is that the structures represent the leavings of a much older population that were later adopted for use by early human societies with no physical evidence remaining of their origins. Without the ability to carbon date the stone structures, we can only guess at the intervening time between their construction and the first records of humans.