12,000 years ago. The earliest undisputed African rock art dates back about 10,000 years. The first naturalistic paintings of humans found in Africa date back about 8,000 years apparently originating in the Nile River valley, spread as far west as Mali about 10,000 years ago. Noted sites containing early art include Tassili n'Ajjer in southern Algeria, Tadrart Acacus in Libya (A Unesco World Heritage site), and the Tibesti Mountains in northern Chad. Rock carvings at the Wonderwerk Cave in South Africa have been dated to this age. Contentious dates as far back as 29,000 years have been obtained at a site in Tanzania. A site at the Apollo 11 Cave complex in Namibia has been dated to 27,000 years. Göbekli Tepe in Turkey has circles of massive T-shaped stone pillars dating back to the 10th–8th millennium BCE; the world's oldest known megaliths. Many of the pillars are decorated with abstract, enigmatic pictograms and carved animal reliefs. Asia Asia was the cradle for several significant civilizations, most notably those of China and South Asia. The prehistory of eastern Asia is especially interesting, as the relatively early introduction of writing and historical record-keeping in China has a notable impact on the immediately surrounding cultures and geographic areas. Little of the very rich traditions of the art of Mesopotamia counts as prehistoric, as writing was introduced so early there, but neighbouring cultures such as Urartu, Luristan and Persia had significant and complex artistic traditions. Indian sub-continent The earliest Indian paintings were the rock paintings of prehistoric times, the petroglyphs as found in places like the Rock Shelters of Bhimbetka, and some of them are dated to circa 8,000 BC. The Indus Valley civilization produced fine small stamp seals and sculptures, and may have been literate, but after its collapse there are relatively few artistic remains until the literate period, probably as perishable materials were used. Azerbaijan The Gobustan National Park reserve located at the south-east of the Greater Caucasus Mountains in Azerbaijan, 60 km away from Baku date back more than 12 thousand years ago. The reserve has more than 6,000 rock carvings depicting mostly hunting scenes, human and animal figures. There are also longship illustrations similar to Viking ships. Gobustan is also characterized by its natural musical stone called Gavaldash (tambourine stone). China Prehistoric artwork such as painted pottery in Neolithic China can be traced back to the Yangshao culture and Longshan