The structure of the Cloud City was quite complicated with almost no symmetry. From top to bottom, from inside to outside, it was like a huge onion with layers and rings. Numerous messy roads were scattered all over the layers of "onion skin," which made people confused.
A joke on earth said that if a group of aliens came to invade and they arrived at the Xizhimen overpass, the aliens would spend a whole day before leaving. And they'd need some luck before even doing that. If the alien race didn't have a good sense of spatial direction, maybe they would stay on the overpass forever.
However, compared with Cloud City, even the legendary Stone Sentinel Maze invented by Zhuge Liang or the ancient Greek Minoan maze in the myth was not worth mentioning.
