Every now and then the dawn of civilization is reenacted on a remote hilltop in southern Turkey. Dozens of massive stone pillars [at this site are] arranged into a set of rings, one mashed up against the next. Known as Gobekli Tepe ... the site is [made] from cleanly carved limestone pillars splashed with bas-reliefs of animalsa cavalcade of gazelles, snakes, foxes, scorpions, and ferocious wild boars. The assemblage was built some 11,600 years ago, seven millennia before the Great Pyramid of Giza. It contains the oldest known temple. Indeed, Gobekli Tepe is the oldest known example of monumental architecture. Archaeologists are still excavating Gobekli Tepe and debating its meaning. What they do know is that the site is the most significant in a volley of unexpected findings that have overturned earlier ideas about our species' deep past. Just 20 years ago most researchers believed they knew the time, place, and rough sequence of the Neolithic Revolution"the critical transition that resulted in the birth of agriculture, taking Homo sapiens from scattered groups of hunter-gatherers to farming villages and from there to technologically sophisticated societies with great temples and towers and kings and priests who directed the labor of their subjects and recorded their feats in written form. But in recent years multiple new discoveries, Gobekli Tepe preeminent among them, have begun forcing archaeologists to reconsider.