What is the oldest artificial canal in the world?

The oldest man-made canal in the world is the Han (Second Sound) ditch dug by Fu Cha, King of Wu, between the Yangtze River and Huaihe River during the Spring and Autumn Period (486 BC). Also known as Hanjiang River, Hanjiang Valley, Qushui and Zhongdu Water. The old route draws water from Yangzhou in the south, to gaoyou county in the north, to Sheyang Lake in the northeast, to Huai 'an in the northwest and to Huaihe River in the north. When the Sui Dynasty dug the Grand Canal, the old road was reopened and the route changed slightly. (The above explanation is based on Ci Hai)