The Oxus Civilisation was an ancient land centered in modern-day Turkmenistan. It rose around 2250 BCE, when a tribe migrated into the area near the Caspian Sea, and started building a civilisation there. They had many, many interesting pieces of architecture some as a few given below:
There were many other civilisations that migrated to Turkmenistan, e.g. Andronovo, Yaz, etc.
A few of the Oxus further went to Iran, and made much change in the Iranic peoples. There is a clear difference in Persian (Iranian) history as the Oxus went south, with all their inventions.
The Oxus people grew wheat and barley. Carts were likely pulled by Oxen or Bull. It was a very advanced civilisation, almost like the harappans.
This civilisation did not last long, though, as climate change occured. As most civilisations, it suffered, and by 1700 BCE, it had dissolved.