& Tornado Alley
In the history of the ancient world Bactria is referenced as the amazing instance of a Greek kingdom far, far from Greece in what is now Afghanistan. That Greek civilization should have penetrated so far into Central Asia is quite astounding. The nature of the creation of the Greek outpost in Bactria is somewhat less amazing.
When Alexander the Great conquered the Persian Empire he acquired the all its outlying provinces including Bactria. Greek forces then established control in Bactria and maintained it after the collapse of the empire of Alexander. Bactria was at first part of the eastern section of Alexander's empire, which was ruled by the Seleucids. There was extensive immigration of Greeks and the creation of Greek cities. These cities were built on the Greek model and included such pillars of Greek culture as gymnasiums and amphitheatres.
Later Bactria asserted its independence and expanded its holdings to the upper reaches of the Indus River Valley. The Greek State in Bactria lasted for another two centuries, until it was finally overwhelmed by the nomadic tribesmen of the area.
Some of the principal cities of Greek Bactria were established on the Oxus River. The Oxus River drains into the Aral Sea.
Paul Bernard, "An Ancient Greek City in Central Asia," Scientific American, (January 1982), pp.148-159.