Shushtar Historical Hydraulic System
The Shushtar Historical Hydraulic System is located in Khuzestan province and Zagreus mountains. The first date of construction goes back to Achaemenids in 5th century BC. The construction process began by king Darius but later it was continued by Sassanid kings and got restored in that time.
The system has different parts and different functions. The incredible fact is that some parts still work!
It actually worked in a large scale, and has been a good sample of technology and civil engineering of Iranian in ancient time. It had to support the water supply and mills and irrigation. The different parts are: water mills, dams, tunnels, and canals.
The most important thing the system was designed for, was blocking Gargar to provide water for the people of Shushtar. This system was inscribed as a UNESCO world heritage in 2009.