The Hemudu culture (5500 BC to 3300 BC) was a Neolithic culture that flourished just south of the Hangzhou Bay in Jiangnan in modern Yuyao, Zhejiang, China. The culture may be divided into an early and late phases, before and after 4000 BC respectively. The site at Hemudu, 22 km north-west of Ningbo, was discovered in 1973. Hemudu sites were also discovered on the islands of Zhoushan. Hemudu are said to have differed physically from inhabitants of the Yellow River sites to the north. Scholars view the Hemudu Culture as a source of the proto-Austronesian cultures.