Located in the volcanic area of Central Anatolia, Kaletepe Deresi 3 was discovered in the summer of 2000 and has been excavated until 2006 The site contains one of the most important in situ open-air Paleolithic sequence excavated in Turkey, and the first stratified Paleolithic archaeological record in Central Anatolia. Volcanic activity in the region generated a number of obsidian intrusions which have attracted humans to the area throughout prehistory. The stratigraphic sequence at Kaletepe, roughly 8 m in depth, presents at least nineteen distinct archaeological horizons representing the Lower and Middle Paleolithic. Tephras in the Middle Paleolithic horizons and the rhyolithic bedrock bracket the time span represented at Kaletepe, The lithic industry at the site illustrates a wide range of technological behaviours, and documents changes in raw material exploitation and artifact manufacture through the Lower and Middle Paleolithic. it also includes probably the oldest in situ Acheulean industry in Anatolia.