In the middle of the 3rd century BC, Zheng Guo, a hydraulic engineer from the Han state, was sent to Qin to advise King Zhaoxiang of Qin on constructing irrigation canals. Qin had a penchant for building large-scale canals, as evident from its Min River irrigation system. King Zhaoxiang approved Zheng Guo's idea on constructing an even bigger canal. The project was completed in 264 BC and the canal was named after Zheng. Qin benefitted from the project as it became one of the most fertile states in China due to the good irrigation system, and also because it could now raise more troops as a consequence of increased agricultural yield.