Göbekli Tepe is an archaeological site in the Southeastern Anatolia Region of Turkey approximately 12 km (7 mi) northeast of the city of Şanlıurfa. The tell has a height of 15 m (49 ft) and is about 300 m (980 ft) in diameter. It is approximately 760 m (2,490 ft) above sea level.

The tell includes two phases of use, believed to be of a social or ritual nature by site discoverer and excavator Klaus Schmidt, dating back to the 10th–8th millennium BCE. During the first phase, belonging to the Pre-Pottery Neolithic A (PPNA), circles of massive T-shaped stone pillars were erected – the world's oldest known megaliths.

More than 200 pillars in about 20 circles are currently known through geophysical surveys. Each pillar has a height of up to 6 m (20 ft) and weighs up to 10 tons. They are fitted into sockets that were hewn out of the bedrock. In the second phase, belonging to the Pre-Pottery Neolithic B (PPNB), the erected pillars are smaller and stood in rectangular rooms with floors of polished lime. The site was abandoned after the Pre-Pottery Neolithic B (PPNB). Younger structures date to classical times.

The details of the structure's function remain a mystery. It was partially excavated by a German archaeological team under the direction of Schmidt from 1996 until his death in 2014. In 2018, the site was designated a UNESCO World Heritage Site.

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