Zhongyuan (Chinese: 中原; pinyin: Zhōngyuán), the Central Plain(s), also known as Zhongtu (Chinese: 中土; pinyin: Zhōngtǔ, lit. 'central land') and Zhongzhou (Chinese: 中州; pinyin: Zhōngzhōu, lit. 'central region'), commonly refers to the part of the North China Plain surrounding the lower and middle reaches of the Yellow River, centered on the region between Luoyang and Kaifeng. It has been perceived as the birthplace of the Chinese civilization. Historically, the Huaxia people viewed Zhongyuan as 'the center of the world'. Human activities in the Zhongyuan region can be traced back to the Palaeolithic period.