Ancient China was built along the two main rivers—first the Yellow River (Huang He) in the north, and later the Yangtze in the south. In the settlements along the Yellow River, people grew millet in the rich, easily worked loess soil. In the south, people grew rice along the Yangtze river, ate a good deal of fish, together with vegetables, especially water plants such as water chestnuts and lotus. Along with dogs, pigs and cattle, people in the south had water buffalos to help work the soil. By the heavy use of human labor, the same area of land in the south could grow about twice as much food as in the north.