Oxus

Although its real ancient name, Waxš, means "the wild one", the Amudar'ya is navigable for about 1460 km, of a total length of more than 2400 km. Its sources are on the western slopes of the Pamir mountain range, where the ancient Silk road crossed into China.

The Oxus separated Bactria (northern Afghanistan) from Sogdia (modern Uzbekistan and parts of Tajikistan), which has also been called Transoxiana. The delta immediately south of Lake Aral was called Chorasmia. It is likely that in Antiquity one of its branches reached the Caspian Sea.

Not far from its sources, Alexander the Great (or his friend Hephaestion, to be more precise) founded Alexandria, which controlled the trade in lapis lazuli.