River boats

Carrying heavy loads on water is far easier than on land: no rocks, no hills, no ridges. Boats were first used on the Nile, which unlike the Tigris is flat and has predictable winds from the north.
 Egypt 3,500 BCE River boats

Carrying heavy loads on water is far easier than on land: no rocks, no hills, no ridges. Boats were first used on the Nile, which unlike the Tigris is flat and has predictable winds from the north.