According to this definition then Iraq’s man-made river (Saddam’s river) is longer at 565 km. the official role of the river was to collect irrigation water from Mesopotamia fertile land all the way to the Persian Gulf, though the real reason Saddam built it was to dry the Arab Marshes as it was difficult to contain the rebels in the marshes. https://ar.wikipedia.org/wiki/%D8%A7%D9%84%D9%85%D8%B5%D8%A8...