Why were canals an important chinese invention?
Well the Chinese invented canals for river transport, the Mesopotamians invented canals for irrigation so since your question is for the Chinese invention, I will only talk about river transport. The inventions of canals allow large quantities of goods to be transferred greater distances in shorter periods of time. It is such easier to transfer the goods on boat than on a wagon. Another thing was that it was relatively safer. There would be bandits and outlaws that would be able to stop a carriage but usually they did not travel on the canals so they would not be able to rob the boat. The boat was also cheaper because it did not require oxen or horses to travel large distances and there could be fewer men required to transfer the goods on boats.
