Amu Darya
The ancient Greeks called the Amu Darya the "Oxus". In ancient times, the river was regarded as the boundary between Greater Iran and Ṫūrān (). The river's drainage lies in the area between the former empires of Genghis Khan and Alexander the Great, although they occurred at very different times. When the Mongols came to the area, they used the water of the Amu Darya to flood Konye-Urgench. One southern route of the Silk Road ran along part of the Amu Darya northwestward from Termez before going westwards to the Caspian Sea.