The Erlitou culture (Chinese: 二里頭; pinyin: Èrlǐtóu) was an early Bronze Age society and archaeological culture. It existed in the Yellow River valley from approximately 1900 to 1500 BC. A 2007 study using radiocarbon dating proposed a narrower date range of 1750–1530 BC. The culture is named after Erlitou, an archaeological site in Yanshi, Henan. It was widely spread throughout Henan and Shanxi and later appeared in Shaanxi and Hubei.