Shushtar was built as a fortified city on the Royal Road, which connected the two Persian capitals — Susa and Persepolis. In the 600s BC, a complex irrigation system began to be created around the fortress. Several complex structures raise the water level in Karuna for several kilometers to irrigate sugarcane plantations in the vicinity of the city. During the reign of the Sissanid dynasty, Shushtar completely turned into an island city surrounded by numerous canals, dams and dams. It’s hard to imagine the system still working 2,500 years later, even though it was built long before the Industrial Revolution. Thanks to the water mills of Shushtar, the lands around have turned into a wonderful green valley with fertile agricultural land. An amazing place has been preserved in the old town: a large pool, into which dozens of channels descend. From the piercing turquoise water, old buildings and embankments rise up the slopes, and plump motley geese swim in the resulting reservoir.