Resident of Iranian Town Discovers Enormous Underground City While Digging Sewage Ditch in His Home

Entrance to the underground city. Image credit: Amirpashaei
But the most remarkable feature of this town is not the well, but the underground city that lies beneath it. The underground city of Ouee (or Ouyi) is a complex network of tunnels, chambers, staircases, air ducts, water pipes, and booby traps that spans three levels and covers an area of about 4 square kilometers. It is considered a marvel of ancient engineering and architecture.