The end of the last Ice Age brings warmer, wetter conditions to the region that will become southeastern Anatolia, allowing wild cereals and game to flourish.
Mobile hunter-gatherer bands begin seasonally converging on a limestone hilltop near the Harran plain, an early social and possibly ritual focal point.
The oldest known megalithic structures at Göbekli Tepe, massive T-shaped limestone pillars arranged in circular enclosures, are erected by cooperating hunter-gatherer groups.
Evidence of large-scale food preparation, including massive stone vessels and butchered wild animal remains, points to communal feasts accompanying construction work.
Nearby communities in the upper Tigris and Euphrates basins begin cultivating wild cereals and managing herds, coinciding with the site's later use.
Newer construction phases at Göbekli Tepe feature smaller rectangular structures with less monumental pillars, suggesting social or economic changes.
The monumental structures at Göbekli Tepe are intentionally backfilled with rubble, sediment, and debris, preserving them for millennia.
The buried mound remains untouched and largely unnoticed for thousands of years, appearing to later observers as an unremarkable hill.
A joint American and Turkish survey team notes the mound and its broken limestone slabs but interprets them as a medieval cemetery, not recognizing their Neolithic origin.
German archaeologist Klaus Schmidt recognizes the true age and significance of the site and launches the excavation that reveals it as the world's oldest known monumental architecture.
Revisiting the site after reviewing earlier survey notes, Schmidt of the German Archaeological Institute immediately identified the T-shaped pillars as Neolithic rather than medieval, recognizing similarities to other early Anatolian sites he had studied. His subsequent decades-long excavation campaign, continuing until his death in 2014, transformed understanding of the Neolithic transition, demonstrating that complex symbolic and monumental behavior preceded, rather than followed, the development of agriculture and settled village life.