Earlier archeologists worked on the assumption that agriculture was a prerequisite to a sedentary lifestyle, but excavations in Israel and Lebanon surprised science by showing that a sedentary lifestyle actually came before agriculture (see the Natufian culture). Further surprises followed in the 1990s with the spectacular finds of the megalithic structures at Göbekli Tepe in south-eastern Turkey. The earliest of these apparently ritual buildings are from before 9000 BC—over five thousand years older than Stonehenge—and thus the absolute oldest known megalithic structures anywhere. As far as we know today no well-established farming societies existed at the time. Farming seemed to be still experimental and only a smallish supplement to continued hunting and gathering. So either were (semi)sedentary hunter-gatherers rich enough and many enough to organize and execute such large communal building projects, or well-established agricultural societies existed much further back than hitherto known. After all, Göbekli Tepe lies just 32 km from Karaca Dağ.