Navathe, the third floor of hell, was known by the sorcerers of the main material world as "Burning Metropolis".
On this floor of hell that did not seem to have an edge, there were no plains, mountains, rivers, hill, or deserts, but only a magnificent city made of iron. However, since the underground fire was burning incessantly the whole time, even iron could be scorched. As a result, most of the iron buildings were in heated redness. Every pale ghost that approached was sizzling with black smoke, as if they would be vaporized into nothingness at any point.
The suffocating smoke enshrouded the sky, and all kinds of devils wandered in the iron city. They were quite in order themselves, but they treated every soul that entered the hell and the demons that had been captured cruelly.