Yangshao culture
The Dadiwan type site in Qin'an County, Gansu sits atop a fan toe produced by a gully that drains into the Qingshui River valley, itself a tributary of the Wei River. The site was originally excavated from 1975 to 1984, and again in 2004, 2006, and 2009. The most recent excavations reveal that humans had occupied the location sporadically for at least the last 60,000 years. The Neolithic cultural sequence here begins with the Dadiwan culture (c. 7900–7200 BP), followed by the Yangshao culture (c. 6800–4900 BP) and then the Changshan culture (c. 4900–4800 BP). The agricultural economy intensified and flourished during the early phases of the Yangshao culture.