The image captures the miraculous moment when the rays of sun hit a rare cloud called a pile cloud, and the angle and other subtle conditions are reflected in a divine rainbow color. (Source)
Persepolis is not the only wonder of architecture in the Achaemenid era. Shushtar is an ancient fortress city in Khuzestan Province, Iran. The Shushtar hydraulic system, a masterpiece of creative genius, dates back to the reign of Darius the Great in the 5th century BC. The Shushtar hydraulic complex was a complex irrigation system consisting of two diversion canals on the Kârun River, one of which is still working to provide water to the city through a chain of tunnels.
This complex includes Salasel Castle, a tower for measuring the water level, dams, mills, bridges and basins. Water cascades down a dramatic cliff into a basin, then enters a plain located south of Shushtar, creating the possibility of farming on an area of 40,000.
“This systematic masterpiece is the result of the technical knowledge of the Mesopotamians and Elamites in ancient times that greatly surprises all viewers. Madame Jean Diolafoa, the famous French archaeologist, in her travel literature describes the Shushtar hydraulic system as the largest industrial complex before the industrial revolution.